According to The Guardian, Deutsche Bank has handed over all financial records of Trump affiliates to Robert Mueller -- sounds potentially bad for Trump. Deutsche Bank has already paid the Justice Department $10 billion in penalties for laundering Russian money, so they're dirty as hell. You connect Trump to their schemes and he goes down.
Also, don't forget that Kushner did a quickie loan with them right before the election for almost $300 million, so who knows where that leads, and Wilbur Ross, our Sec of Commerce is up to his eyeballs in all this as well. If I had to bet, Ross will be the next person Mueller flips.