God ggg, this sound an awful situation.
Agree with others that, while it's not the solution you were looking for and really, as Hula says, should have been the last resort, it sounds as though this could do him the world of good to feel as though he is more at the top of the class, rather than struggling at the bottom.
I feel for you though, it sounds so stressful. I hope he's getting on better soon.