Not sure this is too late for you, Dave. But I thought I'd share my experience anyway having (painstakingly) gone through the research process in last 4 months trying to figure out how to tow a TT that fits the needs for my family of 4 with my X5 and finally being able to arrive at a solution.
Tow vehicle: 2024 X5 50e, rated for 5952 lbs towing and 551 lbs hitch capacity, with factory tow package.
TT: 2024 Winnebago 2326RK, 4510 lbs dry weight; 6000 lbs GVWR; 412 lbs hitch weight. Roughly 23.5 ft. long excl. the A frame up front.
The set-up: I decided to stay away from WDH after calling around and reading online, just in case something happens and someone pulls out a document and wash their hands, although no one seems to have seen any document explicitly advising against a WDH. I had an adjustable, 9.5" rise hitch to bring the hitch ball to the right height. Winnebago manual says the hitch height is 28" and that is about right. There is no need to take squatting into the calculation since the airbag will raise the rear end of X5 right back up after TT is connected. To keep myself safe in cases of severe sways, a CURT 51202 True Course electronic sway controller was installed. For trailer break controller I used Tekonsha Prodigy 3 with a “Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers” (ITEM # TK29FR on etrailer.com). The harness plugs right into the receiver under the dash but need to have the break light and +12V wires swapped.
The first trip was very satisfying, about 250 miles, mostly on highways. Most of the time I was cruising at 65 mph except to pass (!!!) where I'd go up to 70 mph. To be honest, I didn't feel much sway at all even when semis pass me. I did stop once to adjust the hitch ball down one notch, I'd say half an inch, when the trailer was like pulling the read end of the X5. That made the world of difference and remainder of trip smooth.
Hope this helps.