~ What's stopping me from using them to KYC my account and then giving them a piece of the stuck funds?
Even if you asked someone else from an unrestricted country to withdraw the funds for you, the casino will remain doubtful of the documents because you already used a phone number from a restricted country.
You clearly said it here:
So I created a fake number from Hong Kong, and entered it in. It sent me a code and I entered it. Little did I know Hong Kong is also banned from this site (I know I know, I was just in a hurry to place a bet). Now my account is locked and they will not allow me access to even withdraw until I go through full KYC.
Betfury.io, their thread
https://bitcointalk.org/index.php?topic=5276159.0Test all platforms with small amounts first.
You might want to check if withdrawals are reviewed manually before released or not.