I think I'd at least explore taking him back. He's certainly saying the right things and, on the surface, appears to be owning up to his transgressions, and working on learning and growing from them. Were I a coach or administrator, and charged with having input on such a decision, I'd sure want to find out whether this indeed is/was a sincere effort to turn one's life around, and if I determined that it indeed is/was, I'd want to help him to achieve that goal.
It isn't even about the football, it's about helping transform young people into good and productive adults. Cater could well develop into an inspirational role model, or he could revert to previous form. I'd at least want to do my due diligence.