Audrey isn't smart enough to be a "Nina Meyers."
BTW...she (Nina - aka:Sarah Clarke) was a guest patient on "House" a few weeks back. Good actress.
Which is why she isn't going to last a whole three seasons. Incidentally, I think Audrey is also the reason that CTU was originally suspicious of Paul. Remember how Marie used Reza's computer to cast suspicion on him while hiding her own tracks? Same deal here, methinks.