In my own opinion, I will keep the money because to have money now is very hard, so anyway the money comes from, I will keep and use it to give to the less privilege or to those I know that needs helps and our government or none of the authorities are helping, I will give to them, I will just make sure I spend the money wisely but not to myself alone, I will make sure others also benefit from it too, I can't take the money to the authorities because they will also take half or might even share it among themselves meanwhile they don't know how the money was gotten from, maybe illegally or legally, they don't care and you want me to give to them, I can't.
If is not asking what you will do to the seize money but rather he is asking for an open discussion about what will casino do from the money that seize due to illegal sources in which have different answer depending on how the casino management deal with this kind of money.
Normally, it should be reported to Anti money laundering authority so that this money will not cause them a trouble once the authority tracked the money of the illegal source. But I’m not sure if online casino practice this since they don’t have any physical casino while they operate internationally.
Maybe some of this illegal money will go back to their bankroll then just send to authorities when asked for it.