Y'shtola did actually mention Unukalhai while in Alzadaal's Legacy. Obviously this only happens if you've done the quests. But they aren't going to bring Unukalhai in properly unless they make the trial series required. As for Cyella, although I don't think they will make all the role quest mandatory, they could still manage to re-tell aspects of her story in the MSQ like they have done before when bringing sidequest lore into the MSQ.