R1 not responsive even after replacing

I recently dropped my Steam Deck (LCD) and noticed that the R1 button seemed to be broken -- it felt loose, and it while it still worked when pressing it from the top, it was no longer "clicking" and was unresponsive when pressed from the side/corner of the console. So opened it up using the guides on this site, removed the R1 button and found that the plastic bar extending to the center of the console had broken off. I ordered a new R1 button from this site and installed it.

To my confusion, the problem wasn't solved. The new R1 button doesn't feel loose but it's still not clicking and it's still unresponsive from the side. So I assume something else is broken, but I can't identify what it is, so I'm wondering if anybody with expertise on the Steam Deck can help me here. I'm happy to order replacement parts and do the repairs myself, I just need to identify what the problem is!