Right Joycon Charges, but won't connect in handheld mode

Just performed the joycon shell swap procedure. This is the 3rd one I’ve done. First two were just for appearance reasons only, this one was necessary because a friend of mine cracked the original joycon housing and a joystick needed replacement. Prior to performing any work, I connected the joycons to my switch to identify the problem. Both joycons synced as they should when physically connected to the switch.

Performed the shell swap and joystick replacement, but now the right joycon only connects wirelessly to the switch. The joycon charges, but it isn’t recognized as being attached to the switch. I’ve tried reseting the switch, disconnecting all controllers, updating the joycons. Nothing seems to work. Which component is potentially damaged here? Is there anyway I can buy a replacement part to fix the issue or is my friend just going to need to buy a new set of joycons?