Here's my theory:
Lizzy didn't see a place. She saw the traitor. I don't know who it was because I think all the
characters are busy and accounted for but that would definitely make her say "no" and start distressing.
Also, I wouldn't be surprised if there was some sort of connection between
the mallers and
the colony. Maybe its just a "this is our territory and that's yours we'll all just stay away from each other" type of deal, and maybe they just share information. It just seems strange to me that the Mallers are out looking for people right after
Michael and co escape.