James D

1. This is most likely the reason she was denied entry. She had to have entered the US within 6 months of her medical exam. 
 
2. Why you mention her employment and lease in her home country?  It certainly would not help her getting a resident visa for the U.S. and would only be important if she was looking for a tourist visa.
 
Classic case of giving USCIS more information than needed.
 
 
 
 

According to profile: OP is from Nigeria.
If things go south as soon as he arrives and he files for ROC with divorce waiver after never having lived with his spouse I don't think we'll have a happy ending. 
Depending on when the visa expires I would have a chat with the wife and try for counseling. If she is adamant about splitting don't go to the US. 

Hi.
The US Immigration visited our apartment in Houston, Tx, at 6 a.m. weeks after we got my wife's Green card. A guy she dated before we met was an unhappy camper, and a policeman, and had been leaving messages on our answering machine threatening to report us to immigration for having a fraudulent marriage... i.e. just for the GC.
The "officer" came in, was courteous, and only asked us a few questions, like how many bedrooms in the apartment.
We told her about the harassnent and she left without any more questions.

It is illegal to travel to the US with pre-conceived intent to stay and adjust status.  Don't do this.  It's fraud.
 
If you are outside the US, the only legal path for you is to apply for an IR1 spouse visa through the US consulate in your country.  That process starts with your wife filing an I-130 petition for you.  You may travel to the US for short visits, but you cannot wait out the entire process in the US.
 

Hi.
The US Immigration visited our apartment in Houston, Tx, at 6 a.m. weeks after we got my wife's Green card. A guy she dated before we met was an unhappy camper, and a policeman, and had been leaving messages on our answering machine threatening to report us to immigration for having a fraudulent marriage... i.e. just for the GC.
The "officer" came in, was courteous, and only asked us a few questions, like how many bedrooms in the apartment.
We told her about the harassnent and she left without any more questions.

Unfortunately, social media is now on the DS160 and the DS260. The screenshots I shared earlier are from the travel.state.gov page.
I believe that is an official US government page? Please correct me if I'm wrong. 
I remembering reading about the change a few years back... 
https://www.rferl.org/a/new-u-s-visa-rules-may-push-foreigners-to-censor-their-posts/30005463.html 
 

I was answering you question about how it completely possible OP's partner does not have social media as defined by the DS160 but is still able to communicate with the USC partner. 
If instead we are jumping straight to the DS5535, I defer to your experience helping other members complete that form. But, it would be very scary to know that not being on any of the initial apps listed in the DS160 would automatically trigger a DS5535. I then assume VisaJourney could also be included in the list of Social Media Apps... 

The DS-160 does not include WhatsApp as a social media platform, refers to it as a private messaging platform, and states you do not have to include it. 
https://travel.state.gov/content/dam/visas/PDF-other/DS-160-Example_11-19-2020.pdf 
Maybe things have changed and someone who has completed the DS-160 recently can correct me if I am incorrect. 
 

With its extensive social features, WhatsApp is considered a social media platform. WhatsApp is used by over a billion users every month to send text messages, photos/videos, etc. In a nutshell, WhatsApp is a messaging/social networking app that falls under the social media category.Oct 9, 2021

Not really.
 
Countries whose citizens 'obey the laws" and therefore have a very low risk rate of overstay are less strick in determining qualifications for visas.
 
Countries whose citizens repeatedly abuse their visas causes the consulate/embassy to be more strick and evaluate the applicants more thoroughly.
 
In Ukraine, for example, my wife would have had a very low chance to get a tourist visa as a single female with no children and who rents.  Because of previous single females who overstayed.
 
On the flip side, she had no trouble getting a spouse visa because of the low risk of marriage fraud or non genuine relationships. 

I do not recommend this.  If she cannot get a B2 tourist visa, it would be better for the sister in the US to go and visit Thailand so that they can see each other.  "Manufacturing" a suitable husband for her in the US is fraud and any involvement in this can have serious consequences.

The vaccinated are just as likeky to transmit the virus as the unvaccinated. But keep wearing the mask and using the alcohol gel. I  do around others because science doesn't know everything.

The vaccinated are just as likeky to transmit the virus as the unvaccinated. But keep wearing the mask and using the alcohol gel. I  do around others because science doesn't know everything.

The vaccinated are just as likeky to transmit the virus as the unvaccinated. But keep wearing the mask and using the alcohol gel. I  do around others because science doesn't know everything.

Hi.
The US Immigration visited our apartment in Houston, Tx, at 6 a.m. weeks after we got my wife's Green card. A guy she dated before we met was an unhappy camper, and a policeman, and had been leaving messages on our answering machine threatening to report us to immigration for having a fraudulent marriage... i.e. just for the GC.
The "officer" came in, was courteous, and only asked us a few questions, like how many bedrooms in the apartment.
We told her about the harassnent and she left without any more questions.

More voters for the next election.

My husband arrived for biometrics 1 hour early and they were able to take him in immediately. The whole process took 2 minutes.

The biometrics is at Humaitá and the interview is at Centro. They are about a 20 minute taxi ride.

I'm married to Brazilian. I was working overseas so we moved to Brazil. Otherwise I could have been in your shoes.
In 15 years the sister likely will  be married with kids....and a husband. So add some more years. Also, on the positive side, once an immigrant visa is requested, tourist visas aren't so easy to get...

I'm married to Brazilian. I was working overseas so we moved to Brazil. Otherwise I could have been in your shoes.
In 15 years the sister likely will  be married with kids....and a husband. So add some more years. Also, on the positive side, once an immigrant visa is requested, tourist visas aren't so easy to get...

Her paying the full bill has zero bearing in the tourist visa decisions.

Are you sure she does not owe? I have not heard of a hospital issuing discounts to foreigners.

My parents (more specifically,  my mother) has made "jokes" about me petitioning their immigration to the US after I become a citizen. It has never progressed to any serious discussion but nonetheless, it is a majorly hard-cold NO from me. You're an adult. You're allowed to say no. "No" is a full sentence. You're allowed to enforce whatever boundaries you have to with your in-law's for the sake of your mental health and that does not make you selfish. Trust me, I went through therapy for 1 year (as a full-grown adult in her 20's!) and it took me that long to untie myself from those feelings too; I felt like a bad person for wanting to say "no" to my strict/overbearing parents, even after I had moved away from Canada and to the US. But that said, since it's your wife's family, it's really on her to enforce the boundaries. If you want her to grasp how serious this could be for you guys, one idea would be to go together to an appointment with a lawyer and possibly even a marriage counselor to drive home into your wife's head how uncomfortable you are with this situation and how it would affect your marriage/lifestyle.
 
Just wanna add....your wife would be able to petition her mother right away if your wife is now a citizen (which it looks like she is). But your wife's sister will be waiting, at minimum, 1 decade. Most likely longer.

Got my wife's interview date July 16, yesterday, scheduled for Aug. 02. Two weeks' notice! Will have to reschedule due to foot injury.

I´ve never heard of getting a new social security number. She should certainly use the same number.

She has a Social Security number.  Use that one, but unless she still has the card, she'll need a new card with the same number.