Don't take this the wrong way but, go through the trailer again. Been there done that and yeah it sucks. At the risk of embarrassing myself the last tilt deck trailer (that part is just coincidence) I towed 30 min from the house pick up a load driving on the interstate. Got to the location and when the forklift driver put the load on the trailer the coupler came off the ball! It was never locked in. Thought it was riding funny. But I know I flipped the lever to do it.....the wrong way. Talking to my buddy, turns out I'm not the only one who made that mistake with this trailer. Made me feel a little better. ha
Or, seriously, go for a test tow. While there certainly could be something wrong with your brand new truck, the amount of people on this Ram forum that have experienced what you did is extremely small. Unless it has a defect from the factory. It's not the stock suspension system. Chances are greater it's something to do with the trailer or how it is hooked up, or loaded up. I'm curious to see what the cause is as well.