Lucerne CXL 2007 - Unable to pair keyfob

[pnyboy42]

I checked a few threads (Remote 2 not working) and (RKE not working) for help, but I am unable to pair any key fobs. I have 2 fobs, including the original. I think it may be in part due to having a poor battery connection that was just fixed, as I had to jump the car to get it started until I had my battery connection re-connected by my local auto shop. (the negative terminal was loose, per the shop? no idea) I think the jumping may have messed with the keyfob system as the battery likely died or had a surge during a jump, and I do not know enough to fix it.

I have the same issue as listed: "...when I try to relearn remote keys, instead of giving me an activate label, it just blinks once and goes back to the same screen." Sometimes it will beep once, but it does not hold. Otherwise, the car runs as expected. It starts off-rip every time now, which is much better.

I am not sure what to do, and I figured I should ask here before going to my local dealer, as this may be fixable myself instead of dropping $130+/hr for them to only maybe be able to fix it. Any ideas?

I have replaced the fuse in F35. It had a bit of corrosion, but only surface level; Replaced with a fresh fuse. No difference.
I unplugged the box in the trunk with 2 connected cables, leaving it for a few minutes, then reconnecting. No difference.