Chosen Solution
Have an IPAD 4 WIFI that had a cracked screen. Ordered a new one and replaced it with no issues during installation. Reassembled it but the screen is barely responsive and doesn’t work at all in most places.
The old screen was still working just cracked.
Probably the digitizer cable being pinched between the housing of the iPad and the screen. It needs to be folded in a way that it doesn’t get squished when the glass is installed. Always remember to test digitizer before install. You’ll need to replace the digitizer again unfortunately.