Am just beginning to research new vehicle to flat tow behind 2019 Bounder 35K.

The 2024/2025 Buick Encore GX AWD model is one we're considering. Based on owner's manual appears that it would work.

Anyone have any experience with flat towing the Encore GX. Appreciate any input either positive or negative.

Good morning. I agree it sounds a little strange. But I researched it online (ignoring the AI generated response), discussed with local Buick dealership, and reviewed the "Recreational Towing) info in the 2025 Encore GX owner's manual. Everything I found showed the Encore GX is flat towable in the AWD model but not if it is FWD only. 
Not being a mechanic, I'm assuming that the AWD must use different type of transmission.

If you or anyone has any other info, would really like to hear from you

It’s confusing.  Curt Manufacturing lists vehicles for flat towing.  It shows the Enclave and Envision can be flat towed.  Blue Ox also has such a list, but I couldnt find it this morning. 

i thought the issue was with lubrication in the transmission.  

Flat towing will probably run up miles.