Do I have diffuse hair loss? If yes, can I not do a hair transplant? (photos)

You don't appear to be anywhere in need of a hair transplant. You're too young and hair loss is not significant enough. 
I recommend simply continuing with periodic PRP treatment or try exosomes for a more robust response.
Warmly,
Arbella Sarkis, MD 

You don't give your age or say if you've been given a diagnosis for your hair loss, other than saying it's not genetic..Your hair loss pattern does look unusual.  If you've been evaluated in person by two hair transplant surgeons and both told you that you were not a candidate, then most likely you aren't.

The answer is NO. I agree with the doctors you met with. Adding additional hair to any areas that already have significant amounts of hair as you have, will create no problems and risks that are beyond what you can think about. Hair transplants are good for balding people, not thinning hair.