Pay a consulting fee put it on you personal credit card and pay for an hour of a lawyers time to figure it out.

That or go find free legal services and find out.

I consulted 3 different lawyers 4 years ago the first time I thought about a divorce. you can pay them for 1 hour of the time as a consultant without paying a retaining fee.

If you know what the date of filing is then you are entitled to half of what was in the account. You can wait until community property is settled or do it now. As good faith you could send your ex a message & let him know your intentions or let him know after. Either way, you are entitled to 1/2 (that is at the time you filed for divorce. That is when you community of acquets & gains terminated.)