I agree with aprilsue. I have worked for multiple dermatologists for several years and have never, ever, coded a level five! It is essentially impossible for a dermatologist to get this level unless he is spending extensive time counseling and then billing based on time.
As aprilsue suggested, show them by use of an audit tool what level they are actually reaching. Even with the full skin exam, they are often only going to reach a level 2 or 3, and never higher than a 4.
I would warn them that if they consist in upcoding, they are inviting and audit, huge take-backs, and possible fines.