I have a 2014 Defender. Only 1 door was not locking or unlocking using the key fob.
The 2nd fob didn't open it either. I disconnected the battery and drained all power as per your instructions.
After reconnecting, key fob didn't work at all and the vehicle wouldn't start. I found that by disconnecting the battery and reconnecting, I blew the 20a fuse for the fob. I replaced the fuse, the fob worked and the car started. Still have the issue with the one door though.
