I was a bit puzzled as well, I don't know how all the other ones got activated, i remember just exploring and interacting with all the waystones, I mean you come across them a lot before this quest is even brought up. But all of the above-mentioned waystones are now lit-up and the MC's only interaction with them is - "I have no idea how to use this thing". All the tablets are submitted. All the waystones are glowing, 6 of these atleast.
Maybe, i'll try it, see where it goes. Not much else i can do. Maybe if i progress the story enough to get access to the rest of the waystones, and then activate them, then proceed to check in with Erevi again.