Update: when I disconnected the antenna cable, OSX retained my keyboard and mouse in the bluetooth device list, but it had apparently forgotten they were paired. I bought a usb keyboard and usb mouse to figure this out. Deleted the devices from the bluetooth list, rediscovered them, and now it’s working fine.
After I reassembling, my bluetooth no longer works. The antenna connector is definitely seated properly as I heard the click, and it was fully secured when I tried to wiggle the wire. Did anyone else have this problem?