Huh, that's funny... that's because the item never used to check for the quest completion and we added that fix/check in recently which caused this issue. Thanks for letting us know :)
This thread was added on August 20, 2019, with posts from Jagex_Wolf.
Original Post
https://i.imgur.com/cr1LUjc.png
Is there any way to get it without finishing the quest or is it just one of those "just to be sure" checks?
Just to be sure.