A neuropsychologist usually examines people that are alive to assess cognitive functioning after brain trauma I.e. stoke, head trauma, illness. They also provide testing to get a better picture of that persons brain function.
An ME, a pathologist examines deceased people to determine cause of death. They have a large fund of knowledge about mechanisms of injury causing death.
The neurobiologist did not examine TA obviously, but may have a working knowledge of head trauma similar to that which TA indured. It will be speculation at most. IMO