I understand your concern. But there are many things to consider. You do not know if he is an ethical hunter. You do not know if he is a skilled woodsman. You do not know if he would ultimately do harm to your hunting chances, etc. 15 acres is not much land - there is nothing wrong with being the only one to have access to the property.

I would probably not let him hunt - but if your consciense tells you to let him hunt then let him hunt because nothing is as valuable as a clear consciense!!!