Can you help me crunch numbers? F150, 9600 tow capacity

Forget about the 9600 pound tow rating - almost meaningless. Have them check the payload capacity and check that against their estimated RV tongue weight and what they expect to carry in the vehicle.

I used to have an F150 with Ecoboost and towed 5k with it - no problem at all. If I went above 5K, I'd use a WDH. But again, check the payload numbers - that's the real limiting factor.