In the campaign Thornblade on the Xbox One, the quest "Timely Intervention" has a NPC that doesn't spawn or rather is invisible. I've attempted logging out, stepping out of campaign, resetting my Xbox, Quiting the game and going back in and using the get me unstuck option. None of those options have worked, I've asked several people within the area as well if it shows for them and they're all having the same issue. I'm not sure if this is only for Thornblade though, it might be something for Zenimax to check out.