Rob: Driving a Hummer is embarassing enough as it is, so don't think I have no sympathy.
You might try engaging the Four Wheel Drive next time you encounter a situation where you might need to pull off a paved surface with your Hummer. This is typically done, in real trucks, by locking hubs and shifting the transfer case into "4H" or "4L" from "2H". In your case it is probably accomplished by pushing a button. Consult your owners manual.
Doing so will engage the front drive axle of your Hummer, greatly increasing available traction. Most ATV's weigh in the 3-400lb range, so with your trailer it should not exceed 3000 lbs even if it is a heavy weight trailer. I realize that the bloated Tahoe's, I mean Hummer's, already strain to pull their own weight but it is definitely within their range of ability.
I've driven that road many times and there are several areas to pull over. There are also wash roads that parallel the highway. I realize this involves dirt and dust, but I'm sure you would agree that it is preferable to 'chip seal' rocks.
It seems likely that your insurance company may total your vehicle. Since I and the rest of Arizona's taxpayers will be paying for your ignorance, I would encourage you to buy the "Petticoat Option" on your next Hummer. Doing so will provide you with another button activated option that will deploy a long lace covering, a sort of carpet if you will, that will turn any road surface into an acceptable, tranversable surface, practically a Golden Brick Road.