In case you're still working on this, or have the board stashed in the corner somewhere, I just went on a similar journey. I think the 4th try was the charm for me. I had a pad tear trying to change out a hotswap switch for my spacebar, and while I could mostly make it work just by resoldering the connection, there would always be issues with it crapping out on me for a few moments at a time; usable for "F11" or whatever, unacceptable for a spacebar. I tried soldering, resoldering, desoldering and then removing the hotswap socket altogether and resoldering with a bit of wire instead of relying on the glob for continuity.
Ultimate, what seems to have worked is bypassing the PCB's diode with one of my own. It is possible I fried or broke the factory diode, but more likely I just had an iffy connection on its pad, whether from damage or a cold joint, and going the long way round bypassed that, with the new diode keeping it working properly.
For this one, there's no reason that solder job couldn't be good enough, but if you have a bad connection deeper in or a cold joint breaking continuity, it might be hard to notice. Maybe a solder-sucker or some copper wick, and then going at it again could fix it, and take a peek at the other side to make sure everything looks good there.