There are two issues with this.

First, the Eighth Umbral Calamity timeline still exists, even after G'raha alters it. In that timeline, Azem is still dead and cannot travel back in time to Elpis. You can't solve this problem from another timeline. You've just created a Grandfather paradox. That's why Biggs the Third writes 'We shall remain forever on different pages of history─and different books, besides'. The events of one no longer affect the other.

The second, what you're proposing hinges on the idea that everything up to Elpis was always destined to happen and nobody had any free will in the matter. Until G'raha makes the decision to go back and change the timeline, the time travel event is not possible. As a result, there has to be a set of events on Elpis that predate this decision. It can't be a completely closed loop. That's also why Venat says that 'a conjunction has begun to form', and not 'this conjunction was always destined to form'.