With 950 lbs tongue weight and maybe another 50 lbs for the WDH itself, you've only got around 500 lbs payload including driver and passengers, if your expy has a 1500 lb payload like mine.
Was the trailer and truck loaded for a typical trip when you weighed it?
1lbs of tongue weight isn't exactly a 1:1 with 1lbs of payload because it's overlooking the vehicle's rear axle weight rating.
In fact, tongue weight applies a lever action on the rear axle so it's possible that 1lbs of force from the tongue weight could translate into 1.2 lbs of force on the rear axle.