Correct me if I wrong but seems like they really sent your eth but sent it via contract.
Hopefully you have full access to this address, as most exchanges doesn’t allows transaction via contracts, one time I faced same problem but the exchange helped me to restore my ethereum.
Does the transaction reversible if used with contract ? does the sender has the capacity to take back the coins being sent?
I don’t think so, as I can see casino sent him 0.24977624 eth using smart contract
.