I am a certified wildlife rehabber.
Bunnies are tough. There hearts beat so very fast, they are prone to heart attacks from high levels of stress like to much handling. handle the bunny AS LITTLE as possible, keep it in a dark, quiet area with no dogs and cats around. (they have a good sense of smell--adds more stress if they can smell a predator)
Fixing an injured rabbit is just as tough. Their skin (ecsp. wild rabbits) are so very thin. When trying to suture them, the stitches just rip through. As a novice vet tech and niave young adult, I made a doctor prove this to me on a wild rabbit. he was right.
If it is infect broken, he will have difficultly healing, if not becoming unreleaseable. Keep him a short of time as possible. Even wild bunnies kept from nursing babies dont live long in capitivity. I have read much research on this and have lots of 1st and 2nd hand experience.
I may just be coming across like a big meanine but I am telling you this as an experience rehabber and vet tech!
Good luck. I hope he heals up quickly and makes it back on his way!