That could have been the case, but we don't know. They could have legitimately gotten hacked, but then there is no proof for either of these scenarios honestly. All you can do is speculate right now and either way, i don't think it helps you any more or less to get your money back.
If you want to take their word for it, go ahead. But there is also suspicion that they have pulled a runaway scam.
From the start though, you shouldn't have stored anything more than what you could afford to lose on their site. It wasn't supposed to be a wallet.
You can piss off too, they only allowed withdraws of "mined coins" every 24h and that's only if you mined to their wallet, if you mined to your own external wallet they only processed once a week unless you mined more than .01 btc. So really just fuck off with your blame the victim retoric especially when it's fucking bullshit you fucking shitstain.