According to my headcanon, she joined when Solaris was still the leader. This action granted protiection from their shenanigans to herself and her friends, but Florinia didn't know the bottom of it. She got shocked when she discovered that her friend joined a bunch of terrorists and now she is the Flobot we all know and love.
The Team Meteor never gave her tasks dealing with the city, but she is the main responsible behind whatever happened with the trains in the desert. But when Lin got to the top, some inner stuff changed, she got fed up of it and double-crossed them.
But then again, it's just a theory. A Reborn theory.