The ending theme already shows the main team, it's just Goku, Vegeta, Bulma, Piccolo, Shin, so another 3 people in the second ship. I guess Kibito should be needed because he knows how to get to the demon world, but he'll probably stay back with both ships and not come along (unless Bulma turns it into a capsule first).

Glorio learned about the Z team and Gomah's wish by spying on him, yet he claims he heard everything from another demon king. It's a very odd lie, he doesn't want them to know he was spying? We don't know why he was spying on Gomah in the first place, or if he does come from another demon realm at all, but I expect simple politics between demon realms at this point; if not, he's looking for something by himself and everything is a lie. Other than that, I think Shin is just overly suspicious because Glorio is a demon: Glorio never met any of them anyway, he shouldn't know that anything changed. It may be odd that they are kids (or look like kids at least), but he shouldn't have anything to compare to anyway, so Shin shouldn't have a reason to get suspicious - if not for the fact that we know he's right and Glorio is lying for some reason.

Gomah might be a threat but he doesn't look like final boss material. He might have more political power than actual power, and he'll probably serve to move the plot, like with that third eye thing. The doctor sister is more suspicious, Shin just doesn't know she's involved yet.