so hold on, are there other sessions going on on earth at the same time as the beta kids' that might result in the successful creation of a universe, sans the responsibility of being the ones to defeat lord english? if so, would their players be created by ectobiology and sent to earth on meteors from their own sessions' reckonings? would their ghosts be able to appear in the dream bubbles? are all the sessions that other kids may start played by regular human kids and/or always doomed to fail?

The only Session that has Players made through Ectobiology is the Kids’ Session. Ectobiology is the way the game ensures it’ll be played in the first place, so it can send the Temple in the first place and kickstart everything. That being said, SBURB’s specifications are so… Specific, that the great great GREAT majority of people playing the game are doomed to fail by design. However, it IS possible that there could be a Session that wins and makes a separate Universe, but chances are extremely low, and without the Final Frog (Jade’s), it would also create a Cancerous Universe like Karkat’s.

Bubbles, though, it’s hard to tell because, Bubbles are made by Feferi, for her Friends, soooo… It’s hard to say if anyone outside from the people in the Universe A-B-C Session chain even knows about the Bubbles, let alone be able to access them.