Electronic Stability Control Related Problems of the 2018 Audi Q7

Electronic Stability Control problem

I was taking a u-turn under a freeway in my 10 month old Audi Q7. As I was finishing the u-turn a stabilization error message appeared and my brakes went out. I was finishing my uturn and couldn't slow down soi ended up running into the cement barrier with my right back wheel and went onto the feeder. Luckily it was at 5am so no other cars were on the road. Hitting the barrier slowed by car down to 5 mph. As I straightened out my car, the brakes started working again. I had the car towed to the dealership. The dealership said Audi of America had to look at it. The engineer finally came to look at it on Jan 3rd (3 weeks after the accident). He said that they couldn't test drive the car because the control arm was broken but the tests they ran showed that nothing was wrong with the car and told me to call my insurance. I asked how they knew nothing was wrong and they said tests were run. I asked how they explained the error messages (stabilization error and safety error). They said those came up after the accident. They don't the time of the accident so how do they know this?. I took pictures of the error messages and know the timing of that. I asked for a print out of their findings 3 times. It has been 10 days and I still have not gotten anything from them. The car is still sitting at the dealership.