The idiom before you can say knife means very quickly, and in this sentence it is used to describe how quickly someone's name will be taken off the door if they don't do as they're told.
Context: You will become whatever you have to be to make this company run smoothly, or your name will come off that door in a split second!
Hypothesis: You 'll be whatever you have to be to make this company run smoothly, or your name will come off that door before you can say knife!

Is the hypothesis incorrect? (Yes, no, or unknown)?