iamanamericanwife

To know which field office you were interviewed at, look it up based on your zip code back then: 
https://www.uscis.gov/about-us/find-a-uscis-office/field-offices
 
You can file the I-90 now -which is the urgent one- and then file for citizenship 3 months after you move. The average estimated times that USCIS publishes are just for reference; as I said, there are reports of GC replacements being produced in literally a few weeks.
 
And you are still your husband's sponsor unless he's already worked 40 quarters -10 years- or until he naturalizes.
 

1. Class of admission: CR6
2.&3. Embassy or consulate where the interview happened
4. If you don't have the GC image you can file a FOIA requesting one or upload the police report in its place. 
5. If you have the address where you will live in Florida, use that one and file a little before you move -some I-90 have been processed in a few weeks-. I suggest that because if you use current address and then change it, they might send the card to the old one. 

3. See waiting times for your local office here: 
https://egov.uscis.gov/processing-times/
 
4. Do you mean the ADIT stamp appointment? Because you can ask for an I-551 to be sent to you by mail. 

Did you call and said "Infopass"?
Members say it will connect you to an actual human being. 

Had to update the answer after looking through messages in thread.
 
The GC is lost, so stamp is definitely needed for leaving the US.

He must get the stamp before leaving the US if he lost the GC. It's likely USCIS will want to see I-90 filed for lost GC.
 
If N-400 is denied, nothing will happen if he has a valid stamp in the passport.