I don't have any experience with such cases, mainly because I make sure my documents are in order when I deal with mortar and brick banks. At this point in time, your friend can be contacted by whatever authority thinks he did something wrong, but not by the bank itself. My question to you is, has your friend already been contacted by them? Is this a topic︀ posted so you can figure out what comes next? If your answers are yes to︁ both of those questions, I suggest you tell your friend to contact a lawyer, because︂ he lied about his crypto.