I have recently left one of the big 4 firms, where I was an audit manager. I actually wanted to work in industry when I arrived here but it proved too difficult due to my lack of Cantonese/mandarin language skills and lack of experience in industry.
I have been aware of a fair number of senior jobs in industry looking for English speakers with US GAAP/SOX experience so I think your spouse would have a lot more luck than me finding something.
I would personally avoid the Big 4 unless your spouse is looking to work in some form of advisory department. The audit departments are very expat unfriendly (I was the only one in my department!) and it is not a fun experience! Having said this, PwC is far more expat friendly.
There have been a number of redundancies made recently, certainly at 2 of the big 4, so it's not a great time to be looking though I don't think.
I would suggest going to Robert Half and finding work in industry if you can as I have found them to be very good.
Good luck!