iPhone bootloops when home button is installed in new display

I have an iPhone 7 plus that needs a screen replacement. When installing the new screen, it boots up just fine *except* when the old home button is plugged in, in which case it bootloops. When the home button is reinstalled in the old screen, as it came, it is fully functional. I purchased the screen fix kit directly from iFixit, so it’s a high quality part. At the moment, I’m leaning towards an issue with the cables inside the iFixit screen, but I want to make sure before I make a return and buy a new one.