***NEW**Set up to take the fall for the destruction of the gateway, neither of Alayna's options are palatable choices.
It's too late to stop it by the time Security Chief Alayna Baptiste discovers the Supremists are behind the efforts to destroy the Gateway—too late to save herself from mob violence bound to target her since she's setup as scapegoat. She can stay and die or escape into the alien wilderness and probably die anyway.
She didn't actually consider option three—being kidnapped by the Chief of the Kashon—who has had his eye on her for a while as a potential mate.