I think this breadcrumb might be offered before the player can actually do… whatever it’s a breadcrumb for.
I dinged 80 two days ago, in the Ringing Deeps. I was in Dornagal, I think yesterday, and noticed this quest and picked it up. So I headed into Hallowfall with it.
Finally reached the city in “The Bastion of Hallowfall” and while I’m exploring, I found Great Kyron with Anduin standing next to him. I turned in the quest, Anduin phased out, and nothing further happened.
So now I have no breadcrumb to bring me back for whatever thing it is I was supposed to come here for. Maybe it’s gated behind campaign progression? I don’t even know when I’m supposed to come back.