I think Becker would probably be fine.  I had a finance degree, but had to take extra accounting courses to meet the state board requirements.  You will definitely be frustrated at times by some of the concepts, but they do a pretty good job of teaching.

I think you have to be certified in each state where you want to do audit work.  Most of them will give reciprocity for out of state CPA's so your "home" state will just have to send them proof of your CPA to go along with your application.