Hi Tony and welcome to the Jayco Owners Forum. There are some fairly knowlegable folks here who will definitely post here for you. You own a new Jayco and have a tv that's tow rating is less the the GVWR of the tt. I would suggest to set up your tv and tt for camping, then go get it weighed. Weigh the tt, the tv, tongue, and the combined. Find out the GCVWR for your tv. Compare the numbers. Your dealer prob said that your tv could handle the tt? With my limited knowlege, I would say yes on the WDH!
If you are a weekend camper who travels a few level miles to get to the CG, you may be ok. If you plan to do hills/mountains, you may be in the market for a new tv! I will leave it to the experts to answers your questions, but definitely post pics and have fun on your maiden voyage!