Maybe because of I set uncore to max in it, not sure.
Have you tried Throttlestop? If it also doesn't work - you're stuck with experimenting with different BIOS options, as those msrs are completely undocumented by Intel.
Too much undervolt for your silicon) Here's a version without vcore adjustments -
https://ufile.io/oxr6j. BTW, this hack sticks pretty hard, so, once you've run this without "vccin error", you'll get it's effect until a hard reset (but not all other adjustments - they're cleared on soft reset). As a side effect, 2nd load of this after soft reset yields "vccin error" - but this just mean that is still present.
I was going to start a github project for future modifications - can I use your sources as a base? I've asked you in this thread ~2 weeks ago, but since you didn't answer then - I was too lazy to make a complete rewrite before publishing)