Even though those specific narratives aren't the ones that the main narrative follows, that doesn't mean that they didn't effect the main narrative.
It all centers around the idea of the amanuensis: Erasmus' role is largely just that of being an observer, a "Consciousness bearing system" as Jad puts it. He is present to increase the crosstalk between the narratives, so that when the E.K's go off, the bad guys in the main narrative have this horrible premonition of doom, and when Jad and Erasmus sit down and have tea with the friendly faction, their leader has quite the opposite reaction, and helps to foster the peace process.
Like with the "Parking Deck Dinosaur". It appears, then it vanishes, and, despite the fact that the narrative no longer holds it, the people who witnessed it keep the effect from disappearing even after the cause did. Since the causal chain that ended with the Cousin's ship in orbit basically started with the ships first captain having a vision of the Third Sack, it's possible (and Erasmus and Logodhir discuss this at the funeral) that the Incanters specifically provoked the Third Sack to get the second reconstitution allowing the Avout to go back out into the world.
Logodhir doesn't answer the question, but only says something like, "If they did do something like that, then wouldn't you call this a success?"