Tale of Emet [FF14 x Nier Reincarnation event story]

[Slatersev]

The 8uc timeline where they were willing to murder billions just to undo the calamity and bring back the wol?

1) The Scions were all dead.

2) As the short story states, there plan involved killing themselves to, that's how they assumed it would work, at best

Literally weren't going to receive any benefits from doing so. Quite different then trying to staple other living being souls back onto yourself so you can maybe grow taller if you collect them all.