I actually have had similar situations on a couple of the small parcels I hunt. In one instance the landowner asked me, and like you, I felt it was ultimately his decision, so he let the guy hunt on the condition that I have it to myself during my vacation (2 weeks in Nov.). The guy kind of pissed me off though. Removed a bunch of my bright eyes.

On the other parcel, the guy took care of it himself. The idiot never said thank you to the landowner! So he got booted this season and I have exclusive rights.

Don't feel bad. When you hunt those small parcels, it's not like hunting a 400 acre farm. Extra bodies in there WILL screw it up.