RCW,
Remove the word Observation from your internal audit procedure and from your corrective action form.
Years ago ISO 19011 replaced this widely misused word with Finding (a statement of fact (good or bad) from the audit).
Refuse to toe any line drawn by an auditor unless the requirement comes from a legitimate source.
The auditor is not a legitimate source of requirements.
Once you start toeing their invented line the auditor will get worse.
So, warn your auditor not to provide any advice or invent any requirements as a basis for his or her reports otherwise you will ask their employer never to send them to you again.
Change the relationship so the auditor is convinced that you know what you are doing and you are not prepared to be pushed around.
What a stupid waste of time!
John