Magistrate's Cudgel Final Upgrade

[Dwarfare]

I am having issues upgrading the Magistrate's Cudgel to it's top level.

 

I first had it on Rekke (Fighter/Monk, bonded as Monk), brought him to the Oathbinder's Sanctum, went to the deepest level with the massive statue of Woedica and the altar, rested, and the cudgel leveled up just fine, fully upgraded, fantastic.

 

However, I got Mirke (Full monk, bonded as monk (obviously)) later from that free DLC, and I decided that if I'mma have a monk, I'm gonna have a monk that's combating sobriety with her every waking breath. 

 

So, I sever the binding from Rekke, switch the cudgel to her, level it up in two fights to the final stage, go to Oathbinder's like I did last time.  I rest, wake up and... ... ...nothing.  Doesn't upgrade, still says I should rest at Oathbinder's.  I try putting it in a different slot, I try resting at different places in the room, I try restarting the game and giving it another go, resting with food, without, nothing seems to work.

 

Any ideas?