This is my first time to see this scam thread and I'm a regular player on sportsbet.io before I stop last month. I don't encounter this kind of holding funds problem even though I withdraw/deposit back and forth many times within a day. I play an amount more than the OP declared amount. So I believe they will not freeze an account if they don't see any suspicious activity on it.

I'm not being paid by sportsbet and I don't have any connection with them.

You can see my withdrawal/deposit history here: https://bitcointalk.org/index.php?topic=1458034.msg54556238#msg54556238

And show more older transaction if you want.