Brake Disc Caliper problems of the 2017 GMC Sierra

While driving down a mountain road with a 5th wheel attached it appeared that the rear brakes on the drivers side were smoking, I pulled over to allow it to cool. We found a GMC dealership and proceeded there very slowly stopping a number of times to allow the brakes to cool down. 2 miles short of GMC, there was a loud pop and a tire had blown. We pulled over and while calling roadside assistance noticed fire under the truck. We put it out with a fire extinguisher before the fire department arrived. We were towed to the dealership. The brake caliper came apart, the rear axle broke (possibly melted from heat and fire?). Gm initially stated 4 days to repair, now they they are saying 3 weeks as they have to build a new axle. If we had not had the extinguisher the truck, RV and meadow would have all gone up in flames and who knows the disaster that could have occurred if this happened on the mountain road. This vehicle only has 17,000 miles, 11 months old and has had all routine maintenance performed at GMC dealers. I have more pictures but am unable to upload them.

I had the rotors replaced on my new truck at 6000 miles and paid for repairs out of pocket. I continued to hear brake noise. On my way to the dealership on the weekend I was scheduled to have the brake noise investigated and to have an oil change done, I had catastrophic brake failure. A vehicle in front of me made a lane change into my lane and then slammed on the brakes in front of my vehicle at a green light coming to a complete stop from 40 mph to 0 in the middle of the intersection. A car had pulled out in front of him changing lanes from the left lane to right. I mashed the brake pedal to stop immediately and my brakes went soft and to the floor on the second push. When I wasn't stopping. I slammed my emergency brake with my left foot and injured a few toes on my left foot trying to stop before my vehicle. My vehicle did not come to a complete stop. Instead, my vehicle skidded and lightly tapped the vehicle in front of me doing minor bumper damage to both of our vehicles. However there was a Toyota truck behind me, and struck my vehicle directly while I was at a stand still, while the driver was doing over 70 mph when he collided with my Sierra. My Sierra has the pin or part of the caliper that moves the brake pads, completely pushed the piston into the rotor. The vehicle has had brake issues since I paid to have the brakes and rotors replaced at 6000 miles. I have records of the incident and the brake failure from a mechanic and auto body shop documenting the complete failure of the brakes. Directly after the brakes were replaced within another 8000 miles the brake booster on the vehicle went bad and was replaced as well.