Sekhema Asala in the Halani Gates (multiplayer)

While playing campaign with other people, it seems there's a problem with a quest that only count for the first to speak with the NPC: The Halani Gates map, Sekhela Asala follows you to open the bloody gates. Once the first player talks to her, she becomes a follower, and the quest marker disappear. Other players can't interact with her at all.

And when we finish the map, only the player she followed has his quest completed.
So, we had to do the map for each people playing.
It's not really a big problem, it still gives XP and all, but it shouldn't work this way. Other quests work perfectly fine in multiplayer but those with a follower not. I suppose that it will probably be the same with Alva in act 3.