Magenta screen after catalina update

After Catalina update , I got the pink screen on LG display.

I called apple support, they can not even initiate a session via remote view from their end on Catalina.

I have tried:

A few standard apple support articles, including https://support.apple.https://www.tonymacx

and Reset NVRAM or PRAM https://support.apple.com/en-ca/HT204063

Advance: FIX Mojave Catalina MAGENTA MONITOR https://www.youtube.com/watch?v=JlcqAwoNz-Y

Mount Root Partition Read/Write for Post-Installation

https://www.tonymacx86.com/threads/macos-10-15-catalina-how-to-mount-root-partition-read-write-for-post-installation.283749/

I simply cannot paste the file DisplayVendorID-1e6d, which is generated by the ruby, into overrides in the /System/Library/Displays/Contents/Resources/Overrides, When I tried to change the permission into"read&write", it goes "The operation can’t be completed because you don’t have the necessary permission."

Solutions, anyone?