Alright here's my hallucinating mumbling
The worlds from Reborn and Rejuvenation are in fact 2 alternate realities or parallel universes. Everything that happened in Reborn thus far have their ''copy'' that happened or will happen in Rejuvenation. Whats more,
every character in Reborn have their counterpart in Rejuvenation. They mostly share nature and role in story with each other.