Your situation needs to be handled by a divorce lawyer immediately. Your agreements about payments, etc., are civil matters. Immigration will only be interested if he is convicted of a crime.
You can call police if he was recently physically abusive but it is hard to get charges filed unless it was very recent and there is a decent explanation for your failure to report.
Wow, you have going on here. No way anyone here is going to be able to give you a full answer except to say yes, you subpoena records. I believe you need to sit down with a divorce attorney, a good one, and go through this in detail. If money is problem, call around. Many attorneys offer a free initial consultation. Good luck to you.
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