My WTF theory on Zoom, Jay & the knocking man.

So here's my theory. Spoiler warning until episode 14.

• Jay Garrick: The person who we know as Jay Garrick is not Jay Garrick and is an imposter, he is indeed Hunter Zoloman from earth two, who is a friend of Zoom and is working with him.
• Knocking man: Is the real flash from earth two, the real Jay Garrick. That's why he was knocking 'Jay Garrick' onto the glass. He's telling them who he is. The iron mask is somehow dampening his access to the speed force and that's why he can't phase out of that cell. Zoom is keeping him alive so that he can get his speed.
• Zoom: Is Wally West of earth two, who is friends with Hunter Zoloman.

So at the end of episode 14, Zoom stole "Jay" because otherwise the breaches would have been closed and he needed to get his friend out and to create extra incentive for them to re-open the breaches so that he can have access to Barry and Wells again. The reason he 'hand-chested' him to create the illusion of killing "Jay" was to protect his cover.

Possible holes:

• At the time Jay Garrick was the flash on earth two, he seemed to have some experience with Harrison Wells, and the Jay here knows of those experiences, which may have come from torture/mindreading of the real Jay Garrick.
• The person pretending to be Jay looks like the flash on earth two, but we've already seen shapeshifting on the show, so that's not far fetched. However his earth one counterpart still looked like him. That could have also been an imposter and there are other ways to explain it away, however this is still the biggest hole in the theory.

Future:

"Jay", who according to my theory is Hunter Zoloman of earth two, will somehow lose his ability to walk, maybe because of the degeneration of his cells (perhaps Velocity 9 doesn't work permanently). He's dying, and neither Barry nor Zoom will go back in time to save him. That makes him to attempt to do something with the treadmill and that's how he'll gain the Hunter Zoloman powers. He will develop a hatred for both Barry and Zoom. He may help defeat Zoom in this season, while becoming the greater villain for the next.