If you are paying and the group wants you to do anything other than hit the boss and get yourself killed you really don’t want to be there. For a heroic carry, you absolutely are not needed. For many bosses in a mythic carry, the group is at more risk of failing if you are alive than if you are dead.

Super likely. Blizzard has enough power to track down and analyze transactions to be shady. I was hacked once and got my stuff back almost instantly with no fuss.