Quick answer: If you are not an instructor, you cannot allow a non licensed pilot to fly an aircraft under your authority.
If there is no unfavourable outcome in the flight, who knows what happened, and who did what (aside from one of you talking later), so it is a non event. Other than if the plane gets bent, it's on your record, not your passenger's. If you are flying an aircraft you do not own, you are morally obligated to operate the aircraft as the owner expects you are, which certainly would not include letting the passenger land it. Anything goes wrong, the insurance could walk, and you could be paying out of pocket.
Are you competent to quickly fix a landing which has gone awry? Do you want the risk?