If that site is really legitimate, it means something wrong with their system. I'm sure every exchange will move bitcoin as soon as they accept it.
But, when i searched about this site on google. I couldn't find any information about this site, so i think this site is scam.
I've never heard of it either. OP how did you find this site even? I'm curious as to how you came to it as I think you would have found much better options when searching.
But since you sent coins... no if site is bad nothing you can do to get it back. Sending BTC is not reversible.