iPad screen unresponsive even after new screen installed

I have an iPad 2 A1567. The iPad was not dropped nor in any way treaded poorly but one day, it just stopped responding to touch. Reboot, Factory restart, Clean install of new current iOS, nothing seemed to get the touch screen to work. Everything else works just fine from camera to volume buttons to home button to power button, etc. It just wouldn’t respond to touch.

So I bought a replacement screen. After install of replacement screen, the screen problem remained but all other external buttons still work just like before!

I looked at my iPad screen connectors with magnifier and pin 8 on the bottom sock on the bottom row looks like it MIGHT had had dirt. With a blow of compressed air, it is now gone but the screen will still not respond to touch.

I suspect this is a hardware and not software issue but it must be on the Motherboard. Any thoughts about reasons or hardware failures as to why an iPad 2 with a new screen still won’t respond?

Rob