As for how many of these 13 teams that could come out of the Lava Mountain Range in the end…
No one could say for sure!
Don't think that the Zone One Mentor Wei Xu was referring to was small in area just because it was called a zone. In reality, one zone spanned more than 10 thousand square kilometers.
That's why after Qiao Mu and the other teams were brought to Zone One, they were basically spaced out very far away from each other. They didn't have to think of encountering each other in less than four to six hours' time.
Every team was cast off to carry out its mission in its own small area.