KYC helped to track criminality faster even though sometimes casino abuse it, there is a good side of coin about kyc and this is just one of it. Imagine there is no kyc on the account that asked for deposit, the kidnapper would have run away and be on one side chilling with the money and crime free and he will even have the audacity to repeated the same crime again because he wasn't caught for the first time, it will be easy for him to try the second time.
I think casino need to implement limit as well to some of their customers account too. This will save them the stress of investigation. Imagine if that guy was able to pass that kyc, he will move out the money quickly and it might be late to stop him but putting limit on withdrawals will also save them this kind of trouble or better still implement wager atleast one game as some other casino does to avoid money laundering, this is clearly a case of money laundering through the casino.