Did Sally fake the dollar?

I was wondering about this: Right when the doctor is about to throw Burger under the bus about sabotaging the operation, Sally comes storming in saying that he has successfully counterfeited the dollar. He tells Herzog to "see if you can tell which ones are real and which are counterfeit." Herzog then examines only the top 2 in the stack and is satisfied. What if the top 2 were both real? What if they were all real? (Not sure how many real dollars they had as examples). Perhaps they did go on to successfully counterfeit the dollar, but I don't think Sally had it done when he said he did (to save Burger).