Some time ago (at least a year), I did the first of the 2 Blackwood prologue quests "A Mortal's Touch", then put Blackwood aside while working through the various ESO zones in chronological order. Now I'm back at the Blackwood part of the chronology, and I can't start the second prologue quest "The Emperor's Secret", because Eveli and Renna are not at the Riften Mages Guild. Does anyone have any tips on how I can do this quest? It rewards a memento, so I'm reluctant to just skip it and go straight to the main Blackwood quests.

My quest journal says "A Mortal's Touch" is completed and "The Emperor's Secret" is still available to be done.