If he is poaching, and by the OP's posts it seems he is, then the OP needs to distance himself from him. If he gets caught in the field and the OP is there then he is going to have to put up with a lot of garbage to clear his name. Guilt by association. And since the poacher has clearly told the OP is is doing "questionable" things then the OP cannot claim to be completely innocent if he does get caught in his presence.
Say goodbye and let him wander off to parts unknown.
