They did not say how long it takes. I was in contact with 2 different persons from support and I guess they copied a standard answer because it was the exact same one ... I do not know if they check account often but I think it is not the case.
I have checked my statistics for the month: Wagered 1769.55 $ profits 712.28$ Bonuses 175.75$ (for Info I am Platine 1)
May be the reason that you are winning...
I can give just one more advice - to write in the Stake thread with such a problem. If it willn`t help - the only way is to change casino or to create new account. But it looks strange enough. These sums don`t looks serious for the Stake to get negative feedback for it.
PS. the thread link:
https://bitcointalk.org/index.php?topic=2072589.0