Need help - Weight distribution hitch installation pics

If the trailer is really tail wagging on its own, without any input to cause it or wind or bad roads or …..then it’s usually 1 of a few conditions.
1. Trailer just grossly too heavy for the truck. Not the case here
2. Trailer tires too soft/ under inflated.
3. Insufficient tongue weight. Believe you posted healthy tongue weight though.
4. A lot of weight far aft of the axles. Either by ( bad ) design or some very heavy stuff in the back of the camper.
Just suggestions.