Well, I finished it. I saved everyone except one person, and I blame that on staying up waaay too late and having a massive brain fart right near the end. I made a character do one of those stupid things you yell at characters in horror films to never ever do.
I let Ashley, despite reading ALL about the you-know-whos and their tactics, investigate the voice alone AND I let her open the hatch. I screwed up and thought it was going to be Jessica at first(mostly because they toyed with me by finally showing she was still alive in the previous scene), but as soon as I made the choice I remembered they could mimic voices.