Well, we are talking about managing critical infrastructure on a theme park riddled with dinosaurs. Potentially the definition of working under pressure.

I wouldn't think even teenage Kevin Mitnick on Mountain Dew can himself bypass the terminal security (if any), prompt his way to the safety mechanisms, and override their behavior. All while being assailed by a velociraptor.

You didn't answer my question; I just don't get what you are saying is more plausible. Is it that the girl knew Unix at all or something else?

pretty simple explanation: the girl in the movie is more talented than teenage kevin mitnick. if that's a bridge too far for you, i'd recommend not watching the rest of the movie because it's about people cloning dinosaurs using frog DNA.