I know that 51 days seemed like an eternity to you, but over the years I have read terrible stories here where people waited for months and even more than 1 year to get their funds back from various CEXs that implement some crazy measures in order to prevent money laundering and financing of some kind of terrorism.

I don't know how much you care about your personal security, but if I were you, I would create all new documents you used for KYC, and request deletion from their database.