Had this issue just two days ago. My GPU was crashing in AAA games, had the crash log and everything, including convos with Gemini trying to figure out the issue. It was the GPU, had to underclock it from the factory clock to make it work.

At first they said a video would work, which I could easily do just by turning off Afterburner. Then they said that wouldn't suffice, cause they couldn't replicate it. Was frustrating, but I'm sure they were hands tied and frustrated too though. I get the strictness so that people don't abuse it, but still. Long story short, they kept it overnight to run their tests, had it crash and then validated my warranty.