In regards to that poster talking about Doc Scratch's life/death and doomed timelines, I feel like it should be clarified: Game Over is not a doomed timeline. Everybody dying and the kids failing was LE's plan for the alpha timeline all along, even with Aranea's interference. Death and failure is not exclusive to doomed timelines.
Except it was a doomed timeline because if the kids didn’t succeed in creating Universe C then the Cali twins wouldn’t have been born and LE wouldn’t have been able to exist
I’ll just point out that it WAS doomed, but by the virtue of Aranea stealing the ring.
You cannot contact people in other universes if your timeline is doomed (see the first instance of doomed timelines) and there was definitely contact between Alphas and cherubs in pre-retcon universe.Cherubs could have become a thing pre-retcon if John stopped at retrieving the ring. They were a thing pre-retcon, Universe C could have been hatched after GO. But John chose to save the team.
You’re right about characters in a doomed timeline not being able to contact others in different universes.
But the timeline didn’t become doomed until Aranea came back and started messing with stuff, between that point and everyone dying nobody contacted or was contacted by the cherubs.