Good job well done considering the wood has been stressed and so badly cracked, this repair should last forever and it's a "proper job" as ones down "south" would say!
Regards knowing now't about planks you made an old one sound good, what tuning are you using and could you tab the toon for "numpties" like me to try it?
You almost made national TV with your

interruption during the recording process

but you carried on regardless just the same
Keep up the good work repairing and restoring older instruments, it keeps them alive for others to play
Kindest regards
Robert