This is advice that most will agree with given that we are well aware of the reputation of this crypto exchange - but there is always a small chance that something positive will happen and that this story will end happily for the OP. By this, I mean the possibility that the exchange may get a new owner or that the authorities may in some way force them to start working more honestly and transparently.

It may not be big money for someone, but I wouldn’t give up on the $20 000 so easily right now - and I’m glad to see people struggling for years for some goal, no matter how impossible something seemed.