Something is seriously wrong. I would start of getting the trailer weighed empty. Get a scale weight for the trailer axle weight, tongue weight then hook up and get a rear drive axle and front axle weight.
My first gut thought is it sounds like you have a lack of tongue weight if you're getting that much sway. Is there a garage weight limit sticker? Are you over that? Where are the tanks at on the Amped? Over the Axle, aft or fore?
Have you spoken with the factory about what you're experiencing?