Which 3-row SUV should I get to pull a travel trailer?

Get yourself an old Freightliner or International mini school bus, preferably with air ride. Gut and customize the interior. Have a shop build a proper hitch.
Our race shop was towing back in the 90s with a 2500 Suburban locally, and sometimes used my F350 Dually. Well, after numerous close calls, we got an old full sized school bus, shortened it, and made it our hauler. 1st engine, a 6.9 Diesel, wasn't up to the task. That was upgraded to a Cat diesel.