If you do not want to shoot this deer yourself then let your boy or any other first time hunter take him. He does have a bad injury to his hindend and will no doubt not make it a few more years. Animals just like humans when we get a injury such as this get all stoved up and cant get around as we should, we have the help of doctors and the such, wild animals only have luck and responsible hunters to ease the pain of such a injury.
IMO you should do this deer and some lucky new hunter a favor and remove him from your herd.