All they have to do is fake it. Give excuses, charge more fees, reduce hours of operation, and/or close up branches in more populated locations. Making it highly challenging to get all of your funds.

It is kind of like floating your monthly bills with being late, but on a larger scale. There would have to be massive class action lawsuits in order for them to admit they are broke. Before they would ever stop playing the game and admit they are fucking with you.