The new Final Days happened as a result of Zodiark dying due to Fandaniel's shenanigans, which may not have happened in the 8UC timeline. Besides not having Zenos as his buddy he wouldn't have a chance with Emet and Elidibus still around. An undisturbed Zodiark would have kept doing his thing and shielding the planet against Meteion.

Speaking of the 8UC timeline and Zenos, remember that originally the WoL would have won the duel against Elidibus possessing Zenos's body, something that didn't happen in our current timeline because we got pulled by G'raha Tia. While it may have been possible for him to possess his now twice-deceased body it's also possible you can't beat a dead horse too many times.

I'm trying to remember exactly how the threat of Black Rose ended, can't remember if it was Zenos or Gaius's group who destroyed the last batch. There's a lot to cover in SHB's story to pinpoint the exact point.