You know, honestly I find that this scenario is actually, quite possible. I didn't even think about it but now that I do, it has my gears spinning. It is so hard to know what is going on in Jeremys head these days because of the complete 180 they did with his character this season. I am not complaining but I did like him a little better before. He was a lot more balanced, yeah he was jealous and hurt but he didn't act like this at all before. It is obvious he loves Rachel, so much so that is is toxic he has this idea of them together and this I don't know, image in his head of who Rachel is from their history. She has hurt him so much and kind of toyed with his emotions that is just messedan him up. I love Rachel because I think she is truly a kind person she just is dealing with an illness and isn't dealing with it properly and it makes it hard for people to handle her. I do not AT ALL condone Jeremy hitting her by any means but I don't think he is an awful man. He is just as messed up now as the rest of them. He was trashed, out of his mind etc etc. Like I said he never should have layed a finger on her but she isn't an angel either. I always go back though to where I think he does just love her and was very hurt and went about displaying it to Rachel in the completely worst way. I feel like he was kind of shocked and I don't know completely, thrown through a loop a after hearing about the abuse in her past. He felt for her and maybe even thought he understood, really, why she is the way she is.
Sorry I rambled so much there but that is a great theory and I do honestly think it is possible. I am just thinking that after all this happened and he learned some stuff about Rachels, traumatic past and issues there. For him to hear, soon after that news, Coleman saying all of that awful stuff about the woman he loves/loved I think he may have really went for it and did set up the accident with Coleman and Yael. It makes sense to me but like I said I like your theory too because it makes me feel like I don't know Jeremy character like I think I did.
Again sorry that I rambled and typed so much.