My father-in-law, now deceased, was a mentor and long time friend to 5 colleagues, all psychologists. Each month, they would get together for a poker game. It happened that my father-in-law invited me to attend these games, an invitation I could not decline! During one of these games the topic of the Clintons came up. Keep in mind this was in Maryland and all present were Democrats. As the discussion evolved, they began to talk about Hillary. The discussion quickly turned to Hillary's personality profile. Interestingly, the 6 psychologists were unanimous in their diagnosis: Hillary Clinton suffers from NPD (as you surmise) and psychopathology centered on borderline personality disorder. They went further into the causes, suggesting an overbearing father's early childhood rejection of Hillary because she was not male coupled with a verbally abused and submissive mother as probable root causes of Hillary's psychopathy.

I thought you might find my experience interesting. (for clarity, I am not a psychologist; I just played poker with 6 of them)