Just want to answer my own question here again:
Turns out for some reason, probably if your quest log is full, you can not get "Stairway to Wisdom" (Level 62) in the story quest line once you complete the Highwatch cutscene that ends the previous quest. In order to acquire this quest in this state, abandon a quest or two you don't need, then go to Highwatch City Portal (Agora City Portal on the map) in Highwatch and use it to teleport to Meditation Way. Upon loading, the quest "Stairway to Wisdom" should automatically add itself to your quest log.
Hope this helps someone.
