Referral link do allowed for ANN thread.
However, if you are using the forum as a publishing platform to host something really substantial and useful, selling ads in that substantial work is allowed. To be eligible for this, your post must be in a topic that you started, and your post must be substantial and long enough to make the ad seem entirely insignificant. If in doubt, ask me.
But, your casino doesn't accept Bitcoin, which mean it should be moved to altcoins board where it's a place full of spam.
If you want to stay in gambling board, you must accept Bitcoin on-chain, not fake Bitcoin in centralized network or other fake Bitcoin (wrapped Bitcoin).