Sundering stuff established in the Q&A

[Veloran]

the issue I believe that Venat faced was that after the Sundering and after Hydaelyns inevitable death, there would exist no Unsundered to possibly assist those sent to Ultima Thule.

Or she could just have... Not pointlessly killed herself? You'd think the sundering ability would be pretty useful against a being that's already so aether-thin that it's in danger of dissipation entirely. And if some Unsundered are really so important to the conflict maybe she shouldn't have sundered everyone to begin with?

So that explains why she left a gap that only Emet could see, as Hyth would be in Zodiark and thus he’s the only one left with knowledge of Meteion and the events of Elpis. What she didn’t plan on was Lahabrea to “happen to be nearby” with Elidibus and for all three to work together.

As it happens, we don't actually know if WoL even told Venat if Lahabrea and Elidibus were Unsundered. We know WoL told them that Emet formed the Ascians and went into quite a bit of detail about what went down in Amaurot, but even if Lahabrea and Elidibus were mentioned the existence of the sundered Ascians already means that they could have been sundered and raised back to their seats anyway.

Q: I don’t really understand why the Warrior of Light messing around in Elpis didn’t create any alternate timelines. Can you explain what happened?

A: First of all, we’ve left that part up to interpretation.

With that said, my personal interpretation is that the past and present were always the part of the same timeline. Although there was still a possibility for the timelines to diverge, the Warrior of Light was unwittingly acting in accordance with Venat’s plans, which unified the past and present. Another interpretation might be that Venat worked really hard behind the scenes to ensure that the timeline wouldn’t go awry.

Seeing how Argos took to us on our first meeting, I’d say that proves that the past and present were already unified.

There are a few things to note in this question. First, obviously, it's about the nature of time travel and why Elpis didn't pull a ShB. And the first response he gives to that is that it's open to interpretation as to whether or not it even did. Next, he says that his interpretation is that this was always one timeline/timeloop, that even if it was possible for a timeline divergence things worked out in such a way that it didn't happen. He also adds that maybe Venat worked to ensure the timeline didn't go wack.

So clearly, in terms of the question being asked, this is a very vague and noncommittal answer. He's not really answering why exactly there wasn't a split or if everything was predestined. However within this answer he does reveal something very definite - That Venat absolutely wanted for the timeline to remain the same as the one WoL came from. She planned for WoL to act in accordance with her, with the intent to unify the past and present, and may have worked very hard behind the scenes to ensure everything lined up. Whether or not this was directly a result of her actions or was simply up to fate is left to interpretation, but not her desire.