Just Paul

Sure you can try but expect the same result as trying to expedite if you are pregnant.   You should be able to have egg removal done locally and you can bring them with you in a small cryogenic container.  ( Ironically I have done this as a courier for a zoo)

Yes each applicant needs a separate set of original documents.

Are literally that.  Where to you currently get your mail? Where do you currently live? Where do you plan to live?
As a US citizen you have to file tax returns regardless of where the income is earned.  If you didn't have any taxable income during the last few years you include a statement to that effect.
If you have not started the "new job" prior to the interview a Joint Sponsor will be needed.
 

She needs to file an I-130 for each child.

It is certainly up to you.  There is a definite value in less hassle and cost in an IR-1 vs a CR-1.  Most people just want to be together that fastest way possible cost and removal of conditions be damned.
 
Two approaches to consider is:
1) ask the consulate to reschedule
2) to let the NVC do its thing and IF you get a date that means entering before your two year anniversary, do the interview but delay the medical.  The expiration date is based on 6 months from the medical.  I have seen this done in other consulates.  The consulate does the processing and holds it until the medical is complete.
 

It is certainly up to you.  There is a definite value in less hassle and cost in an IR-1 vs a CR-1.  Most people just want to be together that fastest way possible cost and removal of conditions be damned.
 
Two approaches to consider is:
1) ask the consulate to reschedule
2) to let the NVC do its thing and IF you get a date that means entering before your two year anniversary, do the interview but delay the medical.  The expiration date is based on 6 months from the medical.  I have seen this done in other consulates.  The consulate does the processing and holds it until the medical is complete.
 

It exists in statute and was created due to delay in getting CR/IR visas done.  That delay was well in excess of the current (relative) processing times.  It is an option that is available when there are issues preventing a CR/IR visa being issued. It might as well be considered at obsolete since it is so rare. In the last decade it has predominately been utilized in rare cases within Latin American "triangle" countries. 

It exists in statute and was created due to delay in getting CR/IR visas done.  That delay was well in excess of the current (relative) processing times.  It is an option that is available when there are issues preventing a CR/IR visa being issued. It might as well be considered at obsolete since it is so rare. In the last decade it has predominately been utilized in rare cases within Latin American "triangle" countries. 

Doing it the correct way leads to getting the process done faster.   Stream across the border (ie without inspection) and you end up having to leave the country for an indeterminate time to process the visa and a waiver.   It is not a fun or cheap process.  Do it the correct way and there is a chance the steps after arrival go as fast and easy as ours.
 
 
Another poster asked if you filed online.  Your answers help us to help you.  If you filed online then a receipt should have been generated that day.   File a request. (won't go into the the details but it is an automated process but hiccups occur with credit card processing.)  If you filed by paper and didn't do anything like staple, strap, put in a note book or include miscellaneous un needed items then file a  request for the receipt.   If you did staple or similar then you just wait for the lowest bidder contractor to have time to get to the pile of items to be manually scanned. That can be over a month.
 
I've helped out at an immigration clinic in the past and I can tell you that those who entered incorrectly have tons of heartache trying to fix things - well at least in the recent past.  I can also tell you knowing someone that did a k3 nearly a decade ago that it takes the worst things from a spousal visa and mixes it with worst things from a k1 visa.  The brief 2019 occurrences of K3 speeding up I-130 approvals seam to have ceased but since it is free to try feel free to move ahead once you have the receipt number issue resolved.
 
It is a long process but understanding it end-to-end and have patience is the only solution.   In US Immigration the more urgent you want something makes anti-karma  occur in the process.

Doing it the correct way leads to getting the process done faster.   Stream across the border (ie without inspection) and you end up having to leave the country for an indeterminate time to process the visa and a waiver.   It is not a fun or cheap process.  Do it the correct way and there is a chance the steps after arrival go as fast and easy as ours.
 
 
Another poster asked if you filed online.  Your answers help us to help you.  If you filed online then a receipt should have been generated that day.   File a request. (won't go into the the details but it is an automated process but hiccups occur with credit card processing.)  If you filed by paper and didn't do anything like staple, strap, put in a note book or include miscellaneous un needed items then file a  request for the receipt.   If you did staple or similar then you just wait for the lowest bidder contractor to have time to get to the pile of items to be manually scanned. That can be over a month.
 
I've helped out at an immigration clinic in the past and I can tell you that those who entered incorrectly have tons of heartache trying to fix things - well at least in the recent past.  I can also tell you knowing someone that did a k3 nearly a decade ago that it takes the worst things from a spousal visa and mixes it with worst things from a k1 visa.  The brief 2019 occurrences of K3 speeding up I-130 approvals seam to have ceased but since it is free to try feel free to move ahead once you have the receipt number issue resolved.
 
It is a long process but understanding it end-to-end and have patience is the only solution.   In US Immigration the more urgent you want something makes anti-karma  occur in the process.

Doing it the correct way leads to getting the process done faster.   Stream across the border (ie without inspection) and you end up having to leave the country for an indeterminate time to process the visa and a waiver.   It is not a fun or cheap process.  Do it the correct way and there is a chance the steps after arrival go as fast and easy as ours.
 
 
Another poster asked if you filed online.  Your answers help us to help you.  If you filed online then a receipt should have been generated that day.   File a request. (won't go into the the details but it is an automated process but hiccups occur with credit card processing.)  If you filed by paper and didn't do anything like staple, strap, put in a note book or include miscellaneous un needed items then file a  request for the receipt.   If you did staple or similar then you just wait for the lowest bidder contractor to have time to get to the pile of items to be manually scanned. That can be over a month.
 
I've helped out at an immigration clinic in the past and I can tell you that those who entered incorrectly have tons of heartache trying to fix things - well at least in the recent past.  I can also tell you knowing someone that did a k3 nearly a decade ago that it takes the worst things from a spousal visa and mixes it with worst things from a k1 visa.  The brief 2019 occurrences of K3 speeding up I-130 approvals seam to have ceased but since it is free to try feel free to move ahead once you have the receipt number issue resolved.
 
It is a long process but understanding it end-to-end and have patience is the only solution.   In US Immigration the more urgent you want something makes anti-karma  occur in the process.

Doing it the correct way leads to getting the process done faster.   Stream across the border (ie without inspection) and you end up having to leave the country for an indeterminate time to process the visa and a waiver.   It is not a fun or cheap process.  Do it the correct way and there is a chance the steps after arrival go as fast and easy as ours.
 
 
Another poster asked if you filed online.  Your answers help us to help you.  If you filed online then a receipt should have been generated that day.   File a request. (won't go into the the details but it is an automated process but hiccups occur with credit card processing.)  If you filed by paper and didn't do anything like staple, strap, put in a note book or include miscellaneous un needed items then file a  request for the receipt.   If you did staple or similar then you just wait for the lowest bidder contractor to have time to get to the pile of items to be manually scanned. That can be over a month.
 
I've helped out at an immigration clinic in the past and I can tell you that those who entered incorrectly have tons of heartache trying to fix things - well at least in the recent past.  I can also tell you knowing someone that did a k3 nearly a decade ago that it takes the worst things from a spousal visa and mixes it with worst things from a k1 visa.  The brief 2019 occurrences of K3 speeding up I-130 approvals seam to have ceased but since it is free to try feel free to move ahead once you have the receipt number issue resolved.
 
It is a long process but understanding it end-to-end and have patience is the only solution.   In US Immigration the more urgent you want something makes anti-karma  occur in the process.

She can interview in Canada as long as she is legally present there.

A GF can not get temporary or permanent residency in Mexico unless she is a student or has another method.  There is no Fiancé visa there and she would not be able to get it as a family member.  Basically residency there comes in three flavors, RT which is renewable every year, or RP which is a 4 year visa.  You apply for the green card at the INM office after arrival where you are going to domicile.  There is very slight possibility of changing from a visitor visa to a resident visa but technically she has to leave Mexico to do it.  That is harder to accomplish then the US system of converting from a B2
 
I hold a permanent resident visa for Mexico.  When we married Mary was able to get a Permanent Resident VISA very easily and quickly in Hong Hong for $37.
 
Mexican Citizenship is hard to acquire of one of her parents does not have Mexican Heritage.

A GF can not get temporary or permanent residency in Mexico unless she is a student or has another method.  There is no Fiancé visa there and she would not be able to get it as a family member.  Basically residency there comes in three flavors, RT which is renewable every year, or RP which is a 4 year visa.  You apply for the green card at the INM office after arrival where you are going to domicile.  There is very slight possibility of changing from a visitor visa to a resident visa but technically she has to leave Mexico to do it.  That is harder to accomplish then the US system of converting from a B2
 
I hold a permanent resident visa for Mexico.  When we married Mary was able to get a Permanent Resident VISA very easily and quickly in Hong Hong for $37.
 
Mexican Citizenship is hard to acquire of one of her parents does not have Mexican Heritage.

Yes it is no problem traveling once your passport is stamped.  This even applies to "regular" I-130s.   We entered on a Sunday and went back down to Mexico the next Friday.  We paid the green card fee right after getting the visa.

A GF can not get temporary or permanent residency in Mexico unless she is a student or has another method.  There is no Fiancé visa there and she would not be able to get it as a family member.  Basically residency there comes in three flavors, RT which is renewable every year, or RP which is a 4 year visa.  You apply for the green card at the INM office after arrival where you are going to domicile.  There is very slight possibility of changing from a visitor visa to a resident visa but technically she has to leave Mexico to do it.  That is harder to accomplish then the US system of converting from a B2
 
I hold a permanent resident visa for Mexico.  When we married Mary was able to get a Permanent Resident VISA very easily and quickly in Hong Hong for $37.
 
Mexican Citizenship is hard to acquire of one of her parents does not have Mexican Heritage.

She can interview in Canada as long as she is legally present there.

We married less than a year after we met.  We applied 4 months after marriage.  We did live together in Mexico for the last 2 of the months.  
You can file online from anywhere.
 
I know people that have filed a week after marriage and had no issues.   Each case is done on it's own merits.  The key is having the nest evidence submitted that you can such as co mingling of assets, time together, etc.  Letters from friends are not of any value unless you have nothing else to offer.

We married less than a year after we met.  We applied 4 months after marriage.  We did live together in Mexico for the last 2 of the months.  
You can file online from anywhere.
 
I know people that have filed a week after marriage and had no issues.   Each case is done on it's own merits.  The key is having the nest evidence submitted that you can such as co mingling of assets, time together, etc.  Letters from friends are not of any value unless you have nothing else to offer.

I would do this if A) she were dead B) I needed to pee C) it was nearby and D) it didn't have to be in the AM

I would do this if A) she were dead B) I needed to pee C) it was nearby and D) it didn't have to be in the AM

I would do this if A) she were dead B) I needed to pee C) it was nearby and D) it didn't have to be in the AM

YES
As for any repercussions of having the DCF not being accepted - there aren't any.   The USC files the I-130 normally.