Here is where things currently stand, I think I resolved the issue but am documenting it in depth below for anyone in the future who encounters something similar:
After reformatting and then going into DFU and re-flashing firmware and doing a reinstall, I upgraded back to Monterey and did Migration assistant from my time machine backup. Seemed I was in the clear as I had no Kernel panics for maybe 24 hours after booting the machine around 30 times.
The next day after around 24 hours it Kernel panicked again and restarted (like it would do) on a cold boot in the late AM. I did some more research, removed all accessories/TB dock and kept running it to isolate the issue further.
Still more panics.
Called a local Apple repair shop I've gone to in the past and they suggested I try a clean boot without Migration assistant. I'd already been leaning towards this solution because it was the last thing I hadn't done, but hearing them suggest it after I described all my other issues made me more confident about testing it out.
It's now been roughly 72 hours and I have not had a Kernel Panic. I'm on a fresh install of Monterey, literally nothing installed on it and have been booting, rebooting, and restarting 10 or so times a day. As the issue only happens on reboot.
As much as it seems this is a hardware issue I really think something deep down in my backup or OG install of Monterey is causing the problem. Especially because this computer was migrated from a different specc'd 7,1 that I sold, to afford to upgrade to this one. And that 7,1 was originally migrated from a 2019 MBP.
So there is a lot of room for a weird corruption or config along the way. I even ran Apple hardware diagnostics and have been checking the console to confirm things are ok now.
I will update this post if the issue continues but I think it was a software problem all along. Am wondering what I should do about my original system config. I have a similar install on my 2019 MBP and I may do a migration from there, I'm just worried I'll corrupt the drive again though.
But thank god My system/drive/logic board appears to not be failing.. (for now lol)
