"Could my orthorexia be a manifestation of schizophrenia?" "I am wondering if I should get a second opinion"
There's nothing wrong with getting second opinions, but an internet forum isn't the place to get them about serious medical matters.
I'm a horticulturist, not a doctor. What validity could my opinion possibly have? And any real doctors who post here couldn't ethically give you an answer because they haven't seen you, done an exam etc.
Go see a real doctor in person for a second opinion on this. Come here for help on fine tuning what you eat.
I suspect schizophrenia and anorexia nervosa have some kind of link. Years ago I worked with a man who had schizophrenia. His sister had anorexia nervosa and was probably going to die. It was strange how similar their symptoms actually were.