Soft Keys (Menu/Back) Not Working After Screen Repair

At my shop two of my coworkers have replaced 2 different Galaxy Tab E 9.6 LCD/Digitizer Assemblies in the past couple of weeks. Both are having an issue where the Soft Keys don’t work after the repair. They worked before they sealed the screen down, but after nothing is working. I’ve seen something similar before with maybe a Tab 4 and a charge port repair, but this is a screen repair and I can’t imagine it was 2 defects in a row. We’ve checked multiple times each connection and made sure everything was plugged in. Is there certain screens compatible with certain models? Maybe it was, but I’m just wondering if anyone out there has this issue and knows what could be the cause an the fix. Thanks!