It's just me, but I don't think money enters into RS-J's decision at all.
I do think whether or not he's allowed to go out for basketball is a factor, but I doubt Mack would let such a thing cost him a player as obviously talented as RS-J. No matter what's said, call it a secondary issue.
If I was a betting man, I'd guess that a person or people close to RS-J who don't particularly favor the Horns have been in his ear about the UT offense. I suspect he's been told he wouldn't see the ball enough, that UT intends to hammer away with its' running game, and that he has no guarantee he'll ultimately be a wide receiver instead of a tight end. None of those things are absolutely right...or absolutely wrong. RIGHT NOW, nobody knows how the offense is gonna play out this coming season.
I get the impression from just things I've read about RS-J that he primarily sees himself as a wide receiver, that he, like all supremely talented players, expects to see the ball a lot, and that he questions if those two things will happen with the Horns. More specifically, I expect some people, some recruiters, pushing him to other schools have reinforced those doubts with him.
I'm not sure I'd even call it 50-50 that he comes back to his UT commitment. I hope he does, but very few players who officially decommit recommit to a team. I'd hope that UT stays on him for a while to try to change his mind again, but if it becomes obvious LSU, or somebody else, has really turned his head, I'd hope UT would just move on. I don't think there's any sense in beating your head against the wall if its' a lost cause.