Can't add item to creature inventory with weidu

Hello, I've made a tiny mod that adds a custom item to the game. Specifically it's a weapon that should appear in Greywolf's inventory. The item exists because i can summon it via console but Greywolf refuses to drop it when killed.

The code is : //Part 3 (add item to Greywolf)
COPY_EXISTING ~GREYWO.cre~ ~override/GREYWO.cre~
ADD_CRE_ITEM ~sper055.itm~ #0 #0 #0 ~IDENTIFIED~ ~inv5~

I can't find my error anywhere and Weidu installs the mod without any problems. As I said the item gets created but it's not where it's supposed to be.

P.S. Could it be that i just loaded a savegame not a new game? Also Weidu copies the files to override in game directory while the original override file is in documents so which one is the correct one.

Thanks in advance.