Bug/Issue Killing quest target doesn't register to advance quest

This has happened to me twice, though the first time I think an NPC killed the target and I shrugged and just abandoned the quest. This time I know I killed it as there are no NPCs around.


As the screen shows, the target is the Tintic, and if I moved left or right from here the needle swings wildly around to point at the exact spot I am standing. The quest appears to believe the Tintic still exists. It does not.

I sat in the area below where the torches are, used my wand in line of sight to the right, and directed my electric swarm left to hit it. The Tintic never even knew I was there - which may have been the issue?

However, now I cannot complete the quest.

None of the mods I have should affect this, I'm playing intentionally pretty close to vanilla: UI Upscale (double scale the UI for 4k), Recipe Browser (cause all that is in wiki anyway), MM Configurator (why isn't this standard?), and Food Rot Info (cause rotten food is ick).