Regardless if your name is on the paperwork you are required to notify SS that you are working pt for your husband's business. To be clear, even if it's only a few hours per month, you have an obligation to notify SS.

"If you work while receiving disability payments
You should tell us if you take a job or become self-employed,
no matter how little you earn. Please let us
know how many hours you expect to work and when
your work starts or stops."

http://www.ssa.gov/pubs/EN-05-10153.pdf

This link explains how they evaluate work from self-employment.

http://www.ssa.gov/redbook/eng/defin...ility.htm#a0=3

If the CDIU were ever to investigate you, they would have evidence, via these business loan documents, that you were involved in the business. You could owe back benefits, be fined and you could even potentially look at time in federal prison if they were to allege you have committed fraud. This is serious stuff.