My husband and I had an interview with uscis and different answers to a question about an ex-husband. At the time of filing he was alive, so because of that I chose not to say that he was dead but my husband told the interviewer he was dead. Is it too late

It is too late to give the same answer the first time,

It is time to talk with your attorney to try and help work this out

You're supposed to disclose all info. If you don't receive any letter from USCIS in 4 weeks, consult an immigration attorney asap.