Is the OP setting a member limit or using escrow?
If things go well, I will be holding escrow for BitCasino.io

How will escrow work if the OP is making payments directly to their accounts? I think payment should be made directly to a BTC address to prevent anyone from claiming they were not paid
No, sending to user accounts on BitCasino.io is a much better idea to prevent abuse, pretty much mostly from your customers.
I would hold the btc until BitCasino.io has successfully paid users then I would resend the amount.