how to remove quest item stuck in inventory?

I redid the Qimah level in Interlude 2 to get more xp and switch to a better weapon that I'd been saving, and in doing so I ended up with another Vial of Sacred Water quest item. But I can't put it in the fountain again, so now it's just stuck in my inventory. Is there a way to get it gone?

Throw it on the ground in an area and theres two fountains in that area