If no KYC involve and only have wagering requirements involve maybe this can be easily exploit by money launderer since they could still wager the required amount then proceed to withdraw the funds stolen from somewhere. There's nothing impossible if there huge money involve so criminals could still get away with it, unlike if they implement KYC which required other necessary details like providing selfie then provably this could stop this activity from any casino.
As long as I know, money launderer is smart people who will not take the risk to lose their money by wagering it in casino especially if it is about huge amount of money. Even if there is no KYC, money launderer will not be that stupid to launder their money in casino imo. Lets say money launderer is fine with KYC, they will not choose casino due to the big risk. They can split their money into several exchanges, trade it few times (as trading will be safer than gambling).