weight distribution hitch?

Hard call....I'd load it for a trip and pull it and see how it feels. A good weight distribution hitch will also have some kind of sway control which may factory into the decision.

This has been asked many times. Rather than depend on what a bunch of Internet experts have to say. Read the towing information in your owner's manuals for both the truck and trailer. There are those who think a WD hitch is necessary for towing a bicycle and there are others that think that as long as the rear bumper isn't dragging, you are good to go. WD hitches were developed for towing with softly sprung "58 Buicks or old Plymouth station wagons. Modern pickups are much more capable tow vehicles.

The main thing is to get actual weights on the setup to verify tongue weight, payload, etc.

I towed a similar trailer with a Tacoma and never felt the need for a WDH. It was only till I moved up to a 22 with 600+ pounds of tongue weight that I really felt the need. My casita had approximately 400 pounds of tongue weight. I will say a WDH will make the truck steer better in an emergency situation so if he is the type that prefers to be safety conscious, a WDH is a good step to take.