Yes, they are proven scammers. They refund the winning bets, but the losing ones remain

Web3-based casinos are casinos that we really have to research and do research before using them because there are many cases of fraud committed by casinos on behalf of web3.
They have been deceptive since their inception into the gambling industry so we can warn other gamblers against becoming victims in the future.
From this we can learn that not all new casinos can be trusted easily.
Hopefully not too many gamblers will fall victim to the fraud they have done.