>Not really a marital status issue.

Yes, it is. Highly illegal and a good way to end up with multi-million dollar fines and increased federal oversight among other possible issues. Fun thing about reguatlors is when they find one significant regulation violation, they go fishing for more.

>It’s more of an issue where the bank already knows the credit history of one party who will be cohabiting the home, even though they aren’t on the loan.

If they're not on the loan, then they're irrelevant to the underwriter. Doesnt matter if they plan to live in the home or not. She could put him on the title to the property and his credit history would still be completely irrelevant as long as he isn't on the loan.