Sounds like e reasonable fix attempt but I ink the smart firmware recognises when a cell is damaged and then prevents the battery from being used for safety reasons so you will need to somehow wipe that
Might be a longshot but you might want to try update the firmware on your phantom as part of the process it will update t firmware on your smart battery too.
You can also attempt to remove/detach the pcb from the battery for a few hours (the smart part of the battery) as if its anything like the older batteries is will reset the firmware as trhe circuit will run out of power as discussed here
But I have never tried for a phantom 4 battery 
so let me know if anything works
Also when you power your battery on, have you tried to measure the voltage out to chrckchrck if the battery firmware it actually preventing any power to be sent to the phantom?