Yes, I have tried that as well (clean install via the internet recovery, wiping out all data)
I put it back to sleep without restoring anything from the TC backup and got the same panic (with the original OS and no extra APP data restored).
Also not trying to disappoint you but mine as well as yours was working fine in SAFE MODE
There is a simple explanation for that. While in safe mode the "usage" is limited (look at the graphics quality when dragging a window) and the discrete GPU is not used all (integrated one is the one used in safe mode)
Also, it was not returning any error on Diagnostic mode that you can access with the "D key" (but it did return errors on the diagnostic APP that the "Genius" in the store used when I brought it to them)
So running fine in safe mode does not exclude a hardware issue especially one related to the GPU
All my kernel panics logs were GPU-related like the one pasted below. Worth trying to look into your pannic logs for simmilar entries (containing GPU Panic)
panic(cpu 2 caller 0xffffff7f91214953): GPU Panic: mux-regs 5 3 7f 1f 0 0 severity 3 WS-ready 0 switch-state 13 IG FBs 0 EG FBs 0:1f power-state 0 3D idle HDA idle system-state 0 power-level 20:20 power-retry 0:0 connect-change 0 : [3:0:0][PPLIB] Failed Power Play Initialization. TTL Error Message:
I don't know what to say about your warranty case.
Lucky for me in Europe/SPAIN by law the warranty is 2 years (1st year covered by Apple and the 2nd by the seller -- Apple also in my case).
Mine was purchased in April 2020 so they covered the repair cost -- $960 if I would translate EUR to USD.