AUDREY'S NOSE IS THE MOLE!
I figured it out. The woman's schnozz is so big, that it finally took on a life of its own and betrayed her by turning the schematics over to Colette without letting the dimwit know about it.
Either that or Paul isn't really dead and has been playing "hide the salami" with Nina this past year just waiting for a chance to stick it to his faithless wife by framing her.
Another pretentious, teduious summary can be found here.