Some keyboard keys not working

Hi, I recently replaced the battery on my MacBook only to find that some of the keys were triggering other keys around them as well. I did unplug the keyboard during the battery replacement, so I suspected the connector was possibly bad. Now I’ve replaced the keyboard, and am encountering the opposite issue where certain keys are completely nonfunctional. Attached are microscope pictures of the damage I suspected on the old connector, and pictures of the new connector in case there’s something I don’t see. It looks very different than the old one, but some keys work so I’d assume that’s not related? Any help is appreciated. Thanks!

Edit: I did replace just the keyboard, not the full assembly.

Replacement Keyboard

Replacement Battery

It seems like only the power button is working now. I'm new to all this, so I'm completely guessing here, but is the power button handled on the same IC as the rest of the keys? If it isn't, does that mean I have a board issue?