I'm still holding with the idea that John Henry did not jump the future. I still believe he tricked Weaver into jumping so he'd be free to go confront his Kaliba brother and protect Savannah. And I think the fact that he didn't jump will be deduced pretty quickly, leaving where he might've gone as the mystery.
"Gymnasics ends at 5:30."
I think Savannah's going be picked up from gymnastics a little early by an odd man in khaki trousers and a light blue shirt. Ellison will figure that out, but it'll be too late — John Henry will have already vanished with Savannah and there won't be any riddles-for-clues in this game of hide and seek. Since Sarah and Ellison both have a stake in finding them, they'll be forced to work together.
It would be way more fun if she just pulled a gun and gave him until the count of three to figure out where the metal took the girl, but I kind of doubt that'll happen. Anyway, I'm reminded of this exchange from when Sarah was heading off to the chess tournament:
"Mom, it's chess. You don't know anything about chess."
"I know a bit about Andy."
Ellison may not understand the game he's been playing, but he does know a bit about John Henry. He also knows about the worm attack, the Cyberdyne code base, the "brother" AI and he's actually played hide and seek with John Henry before with Savannah. All of that that makes him useful to Sarah. Between what she knows about Kaliba and what Ellison knows about John Henry, they'll be able to figure this thing out.
It'll be a tense and temporary alliance born of necessity, but maybe, just maybe Ellison will find some redemption in the process (and finally have a little fucking faith in Sarah Connor). And then he can get a bullet to the head... Or go paint a picture for the cops and join Silberman in Pescadero ;)
Okay, fine. When it's all over, he can go live happily ever after with Savannah and the widow Dyson (yeah, she'll factor into all of this because of Danny and Kaliba).