Look at it from the AG's point of view: here's a guy that's a convicted child trafficker and pedophile. We know how he moves his money around, and who is in his network. We know the people who have "donated" to his "charity" and how much money has been moved around. We know he was arrested, did some sort of "jail time" in Florida and was released quietly and quickly. We know that the lead prosecutor on the case was told to drop it as Epstein was "connected to intelligence". We know that the bank continued doing business with Epstein well after the "jail time", and continued doing so for over a decade.
Why on earth wouldn't you want the bank to be held partially responsible? Here's a bank that knowingly did business with a convicted human trafficker and pedophile....and continued doing business with him after his sentence and release.