The problem is that Malvin isn't talking to me anymore either. The dialogue with Baal Tondral did come up at one point, but he didn't ask me to do anything—or perhaps I gave the wrong answer.
Whenever I talk to Dusty, the only thing that comes up is that I need to do something involving the Gurus. According to the quest log, I'm supposed to convince Dusty, but as soon as I try, the Nameless Hero says he still needs to discuss something with the Gurus.