Thank you. Keeping the previous plist untouched, I modified the 2 values per instructed.
View attachment 4767
SMBIOS is also correct:
View attachment 4768
Cleared NVRAM from disk and booted from USB again, with no external display attached.
So we got the black screen again at the same time in the verbose, but now the display FADE (as it should) to black instead of crashing to black. Here's a video:
https://www.dropbox.com/s/eivx48j4b0sjqmk/20220110_174004.mp4?dl=0
For comparison purpose, here's the old boot before:
https://mega.nz/file/BA42VRYA#9IbueeMaojb1AMMsEHflQBY05srYMwpi74LMk4QIHAE
I changed device-id back to 00000000 and got into the system @ 1024x768 resolution, figured TeamViewer was being dumb again and wasn't logged in to my account and logged myself in. Also noticed battery indicator is working, audio is not (no audio device whatever's) - no big deal, not the priority ATM and off-topic (I'm sure I could pull it off with some time, with Clover I succeeded. FYI, Lenovo SPECs says Conexant 20671 but Linux cat /proc/asound/card0/codec#0 | less return Conexant CX20590 (just tried it again)
I tried all the alcid bootargs yesterday and no one worked lol)
Anyway got TeamViewer fixed, then changed the device-id back to 16010000, rebooted and black screen but TeamViewer was definitely working and viewable this time @ 1366c768 still. HD 3000 report 512 MB too instead of 4 MB (TeamViewer laggy and glitchy still but idk, High Sierra TeamViewer is outdated anyway and using it on an Android phone too).
Also played with the brightness slider again, confirming that the screen brightness is maxed out indeed and not at zero.
Hope this helps!