Warranty Work Question

[mps at usol.com]

Greetings...

I am scheduled to repair a piano for a client of mine. I was just 
informed by them that it was to be paid by the manufacturer/dealer. I 
was contact via phone with the manufacturing company and they have 
sent me a form in which to fill out for this repair.
Now the question...
I have a very good business reputation with this client and would hate 
to lose them. I am prepeared [even have scheduled a date, (this 
Saturday) to make the necessary repairs]. But if the company tells me 
they can't pay me after all, I am out the money. If I don't pull through 
on repairing this piano, I could potentially damage an otherwise good 
business relationship with a client. I am well aware that this is a word 
of mouth business.
What would you do?
Also, this warranty form I need to fill out is asking me to make the call 
if it is a factory defect or a defect in workmanship of a previous 
technician. I DO NOT want to point fingers at anyone!
What is a new technician to do here?  So many variables I guess.

Thank you for your time

Mark

Mark's Piano Service
mps at usol.com