In English, it doesn't sound right. Winning the casino? It's like winning at the actual casino,, and you'll become the owner. This should be improved and made into something like "Win against the Casino". This way, it indicates that you have won positively and are no longer in the negative.

Anyway, I agree in the sense that you won against the casino because you are no longer negative, BUT if you are the type of gambler who doesn't keep track of wins and losses, you couldn't say that you have won.

Maybe the best way to say it is when you don't need to gamble anymore and your goal is not to win against a casino because there's nothing to beat.