[travelin texans]

With the 298BHWE it's not 28' but most likely 32-34' from hitch to bumper with a tongue weight of 1000lbs or more.
Your truck payload of 1667 doesn't leave you any room after you add the 800lbs you've stated for people/pets, the tongue weight alone will exceed the payload by a couple hundred pounds BEFORE you add the weight distributing hitch or 1 bag of potato chips into the RV.
Your truck will pull it, but nothing ruins the camping experience worse than a stressful screaming engine white knucklehead towing experience to your campsite, BTDT!
Unless your buddy at the truck dealer has been towing RVs in excess of 40 years like a few, possibly several, on here he doesn't know what RV length/weight that truck is capable of except what they advertise.
The same with the RV dealer you're about to deal with, their goal is to sell you as much RV as you're willing spend money on & will swear your truck can handle it, believe me they don't know or care as long as they sell you whatever you want.
Good luck to you & be safe!