The other humans are probably just beginning meetings to discuss an alliance with the aliens. (thnk non-agression pact) They would offer the people in jail in as human sacrifices.
Plasma Weapons Well, since we have alien tech, we could get around having that problem. Or We could just have it firing the plasma itself. I like the idea of having a small layer of metal around an elerium slug, that way, there's two layers of damage - one from the plasma, and the other from te impact of the slug.