John,
You haven't told us what type of an audit this is, AISC-annual or 3 yr, customer for job approval, city, state, etc. But, unless this is something that you had in writing in your QC manual to set your paperwork off to know it is officially yours and your guys have met your company qualifications then I don't see where this auditor is coming from. This is just total nonsense.
Have a Great Day, Brent