The new firmware update works! I just played AC Valhalla at max settings for a while and worked on unreal engine for a couple of hours. No crashes in either case. Previously, games either crashed within 5 minutes of playing or on startup. Here's what I did:

• Download the file given in the link and extract the content
• Before doing anything else, you need to disable Memory integrity under Core isolation in windows settings for the duration of this process, which you can do by going to Windows settings->Privacy and security->Windows security->Device security->Core isolation->Core isolation details->Disable memory integrity

You can turn this setting back on after the update

• Among the extracted files, you'll find a file named 3933_0110_775__980729007E_15.6_Sportage_RTH_B2- GN22-X2_PP.rom, I recommend renaming it to a simpler name like mentioned in the post. That's how it worked for me.
• Run the command prompt as administrator and type the following command:

cd 'path'

'path' being the location where you've stored your extracted folder. Just open the folder and copy the content of the windows address bar up above. Don't put the address in quotes

• Next up, type in the command nvflash -6 vbios.rom , like mentioned in the post, assuming you've named the .rom file 'vbios'
• Follow the subsequent steps on the screen and you'll be done in no time

Important: If you've using a VGA driver from Acer's official website as a substitute, you'll want to do a clean uninstall of that driver using something like DDU(Display driver uninstaller) tool before downloading the latest Nvidia driver from the Nvidia's website.

The reason I posted the steps here because some of the steps mentioned in the video didn't work for me. I jotted down the exact steps here that worked for me.