I got the email from "Roobet"
The email give me information about instant deposit bitcoin, did this feature will be no confirmation for the transaction of bitcoin.
You can get a problem if someone using "double spend" the transaction.
How, you selected the user for instant transaction, did the player need to wagger/deposit a minimum amount?
Instant deposit works if you have sent Bitcoin from your wallet and it is immediately credited to your account and does not require confirmation. AFAIK, anyone can enjoy this instant deposit feature as long as you are registered on the site and make deposits in any amount according to the requirements.