Romex Wire In Commercial Project 1

We were called in to help a customer that was in trouble with the State Fire Marshal. They have a Physical Therapy business and lease the space they are in. They are also affiliated with a local hospital. We have built all required fire walls and are complete with our portion of the work. The problem is there was Romex wire above a lay in ceiling. Our electrician has changed all the romex above the ceiling as directed by the inspector. The problem is where there is a transition between the junction box and the wall or top of studs. The electrician says that a small piece of romex can be visible between the wall and the junction box and the Fire Marshal says absolutely no romex can be visible. Who is right and where in the code can I find the answer? As is evident I am not an electrician.

thanks.