Chakyash: By googling exception_access_violation (3221225477) you'll see a lot of people that had this kind of crash since game launch. And the most common solution I could find was to download MSI Afterburner and downclock your GPU just a bit even if you never overclocked. You can try that and see if it works for you.
Zazz1022: Interestingly enough this seems to work when I down both the memory and core clock down -20, but only for an hour or 2 at most. A start, but still not a solution. Might just have to experiment some more with afterburner and find that key configuration.
I guess you have your answer there. Downclock it even more and increase the fans speeds in MSI Afterburner, then see how it goes. What is your 1080 Ti model and how old is it? You may need to change the thermal paste. Judging by these high temps, I would guess it's a blower-style Founder's Edition card. Not sure if it's that easy to change the thermal paste on those.
Maybe The Witcher 3 is more demanding on the GPU than the other games, especially with the HairWorks enabled. Personally, I wouldn't run the GPU over 82ºC for such long intervals. I'd rather have lower performance than high heat and fans noise. Try testing with FurMark too - it's probably the best GPU stress test and will heat up the card very quickly, but don't run it for too long.