WR, I wouldn't contact him about the account change. He's a grown man and can figure things out for himself. He should have set up his own account after he left. You've already had a discussion w/him about this a while ago. If he contacts you, I think I would ignore the text since he's been advised previously.
Time for the man to man up and face the consequences of his actions.
WR, it's a rocky road when trying to settle up financials and divorce issues, but I promise you, it will get better.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
