Neutral wire arcing

This is a 12 month warranty inspection. This builder does not allow me to inspect the electrical panel during the pre-closing inspection. The homeowner has had the electricians out to address some defects in the laundry room electrical supply. They never bothered to open the electrical panel.  What I found was a neutral that got so hot it turned the copper blue and melted the vinyl sheeting material that insulates the copper conductor.  Still think you don’t need a warranty inspection on that new house that was inspected by your city or county?