It does look like hacking all around. In a situation like that casino is not the guilty part, neither is the user, it is the hacker that is guilty and the common enemy. Normally casinos wouldn't want the fact that their users could be hacked easily and their money would be taken, that is not something casinos would want get out, so they wouldn't want something like this to happen to any of their users. Users wouldn't want to be hacked as well.... that is pretty obvious.

So, there is really no guilty part here. What could be done and should be done is to follow up on who stole it, check who and how reached the account together, and create a lawsuit to whoever has done it. Usually on crypto world when hacked people don't really do the legal way but they really should do it if they can.