Well if he is off the ventilator he is NOT brain dead. You can't breathe without function of the brain stem, and if he's breathing without a ventilator, then his brain is at least that much alive.
However he may not be at all conscious. He may be in a persistent vegetative state. If that's the case, he may or may not wake up.
Mind you, I am not a neurosurgeon or a neurologist. I suspect that the group of physicians taking care of him know exactly where things are and what's going on, but at the request of the family are not discussing it with the media. The episode where someone tried to sneak in there may have something to do with that, or they may just wish for privacy, which is entirely understandable. This is tragic enough for them without having to be answerable to folks whose business this affair essentially is not.
We'll just have to wait for more real information. What we have now is guesswork. As Pete said.