Replaced display, now keyboard inop and display working intermittently

Hi there, I have a 2015 A1534 that I purchased with a bad display. Replaced the display and it now is completely non-responsive to keyboard input. This laptop was not subject to liquid damage, but rather an impact. I replaced the display and it will boot when connected to power, and the display was intermittently displaying. So I figured I buggered up one of the cables and ordered factory replacement cables from PBM. Well, cables are now in the computer, and it will boot and output a display to an external monitor, but all input from trackpad and keyboard is not recognized, also the display is not showing anything.

Interestingly, when I do an SMC reset, it beeps as if it has been performed, so I don't understand what the issue could be... Any suggestions?