I'm pretty sure they were making a nice income of 100,000$ / month. if not more.
why they close ?
no,they surely were not making 100.000$ a month
and they had a couple of hacks prior to the closure
not sure if it was a hack or just a pretext to close the site but nevertheless,they closed shortly after
also there was a whale betting one bitcoin a pop and slowly draining their wallets
on the plus side,this proves they were legit and paid fair and square,also they didn't leave any outstanding debts
or scam accusations behind,it is just that the business didn't go as planned