We will never know because the casino will never say how to check someone's account or what will make them block one account. We can only assume and therefore, it's better not to risk something that can be fatal to our account because it will be difficult for us later.

Casinos don't want to get involved with anything illegal and they always make sure that everything is under their control. Money laundering, hacking and other illegal stuff is something that casinos don't want. It is the casino's responsibility and we gamblers not to do anything suspicious.