Went back and redid these quests with an alt with the following results
1 - Rane the scout appears to give you the ten attuned pelts when you accept the quest from her to kill the Than'kuk scouts . They just appear in your inventory with no accompanying dialogue and are attuned.
2 - Taking the quest from Fibble and attempting to gain more pelts does not work.
3 - simply deleting the pelts given to you also does not work
4 - Deleting both quest and pelts and retaking quest from Fibble does then work but with one obvious error. The counter is set to ten but after killing one wolf and gaining one pelt the counter immediately shows 10/10 and the quest updates.
Hope this is of use in debugging that quest.
I have tested this on blight and it works just fine. So, I have no idea what the problem with it was when you got it.