I don't really understand... What were you expecting?
It's a casino. Their only goal is to make money.
If you're a big player that means you made big wins. They want to check that those wins are legitimate before paying you out.
It would be the exact same thing in a real life casino. If you win a too high amount they will make you wait so they can analyse the pictures taken by cameras to be sure that you haven't cheated.
That's just to protect themselves from new hackers and bug exploiters that's all. Nothing unusual.
No.... They merely excuses not to pay out. Phone off ? No email reply ? Come on dude.
I'm not trying to defend fortunejack, but it is a common practice on gambling sites. Casinos has the right to check all withdrawal (if needed) before they release it. Bets investigation does not mean that they excuse to pay, lets just wait for them to finish the investigation. Indeed, waiting is suck but this is the only thing that players can do.