That's why I also hesitate to use bank to keep my funds from crypto because they will surely freeze your account with out any reason and their reason is cyber crime or because of anti money laundering law. Why not go to your bank and ask why your account got frozen so that you will know what is the reason for this.
So how are you exchanging to fiat. It is a really old thread and he did not update about the situation after that, i do not think that he will be under any problem if he has not done anything wrong and all you need to do is to approach the bank and sort out the issue and be transparent as you can and have a response to every question they ask about the funds you are getting in your account.