I'll note, first, that everything in the Metalworking + Forging menus fits into one menu.
I opened up character Novrus to check this concern.
Metalworking in the current version already goes to the letter "O" so that can't be true. IIRC that is the last letter that the UI can display. 1-9, 0, A - O is all that fits.
Also my current copies dont have duplicates of woolen menus.
I suspect something is out or order with your install. Recommend moving all your existing diy_* to a subdirectory then doing a fresh install of the BAC.
It could be in your editing that a category tag was damaged. The file would read the previous category assigning the menu item to both.