I never knew that someone can use casino to hide the origin of fund. Although if not for a bad intention of a case of stolen fund or hacked fund I don't see any reason why someone would want to go through that process why there are just simply ways to send fund and trade through P2P and cashout your bulks.
No I don't think somebody can hide there funds on Casino without traceable because there is always a wallet address that would be generated on every deposit so there is no way a transaction will happen on that wallet without being visible to be tracked, so I don't think casino is a place were somebody can hide there money after performing some illegal activities, though it can only happen if the casino is not a kyc enabled casino because somebody can easily use fake details to register and carry out there transaction without traceable because if they track the account they would obviously be going for anonymous person, so now with the enforcement of kyc on casinos it will be very difficult for those users with bad intentions to use it because all there details will be there and will be very easy to track, perhaps that's one of the advantage of kyc Casino.