Will my boyfriend be able to re-enlist in the Marines with osteoarthritis?

We recently discovered that my boyfriend - who is currently at MCRD training to become a Marine - has osteoarthritis. He is going to ELS (Entry Level Separation) probably sometime next week, thus he'll be able to come home. He also has pack palsy, but that will heal with time. Does anyone know if he'll be able to re-enlist...in any branch of the military, once his arm heals from the pack palsy? It's his dream to do Infantry so if he re-enlisted, that's what he would want to do.