What if my application fall in audit ... PMP

NOTHING :) :) :)
Remember...it's easy...it's only time consuming...and if something has to be done it has to be done :)

Don't be surprised. This is the correct reply to this question. Nothing.
Just like you, I too was really scared for the same. I was not in india (from where all my references were ) and if it happened it would have had created lots of extra work for me.
And that is what exactly happened :) :) :)
My application did fall in audit. I filled up my application with lots of deliberation. Received the acknowledgment and instructions on how to pay and then on a cozy comfy beautiful early morning I decided to pay :)
Payment accepted ... and nothing happened ... then i opened my PMI membership home page and found that "your application has been picked up for an audit" and the instructions to be followed. And the horror looked like this ... ha ha ha

Trust me for two days i felt totally lost realizing at the end off the day that if something has to be done it has to be done


AND TRUST ME IT WAS NOTHING ...

1. There were three forms for three references. PRE FILLED. You or the references do not even have to fill those forms. 
2. These are soft copies. Download them.
3. Mail them to the respective person.
4. He/She has to take a print out and sign it. Put it in an envelope. Sign the envelope from outside and post the same to you. 
5. They can give it to you by Hand. You are not supposed to open it. 
6. Collect the same from all.
7. Put all of them in an envelope. Write address mentioned in the instructions and post.

THAT'S IT :)

now your work is to wait. they say it will take five working days from the day they receive it and believe me THEY ARE QUICK. 
        In my case i received two emails. Sent at the same day same time. One saying your application has been received and the other saying it has been cleared. You can now go ahead and schedule the date for the exam. 

THE ONLY TURBULENCE IT CAN CREATE is 

it will affect you plan. if you were planning to give the exam immediately after paying, you will not be able to do the same. 
so my advice on this
    Fill the application well in advance and Pay. So that if your application fall under audit you have sufficient time to follow the above procedure and it does not affect your preparation schedule or does not disturb you anyhow. It is easy but it is time consuming. As such you have one year to give the exam once your application is accepted. 
    i am sure you will be ready in an year :) :) :)