You can mount it to the bumper of a Whitehawk as long as you reinforce it with Mount-n-Lock Safety Struts.
They're only $75.
I just bought a pair and installed them on my Whitehawk. I now have 3 bikes mounted on the bumper.
Here's my thread on the install:
2015 Jayco WhiteHawk 28BHKS Summit Edition
2016 Ford F-150, 4x4, 3.5L ECOBOOST, MaxTow, Supercrew, 6.5FT, 3.55 axle