As implied, choice of doctor and institution is a very important consideration.
Treatment choices depend largely on clinical stage and whehter it's low risk (usually defined as PSA 10 or less, Gleason score of 6, and clinical stage T2a or less), or whether the cancer is Intermediate or High risk which involves Gleason scores of 7 and higher.
Unfortunately there are a lot of gray areas with all PC tests: Depending on the quality of equipment used, some of the diagnositic scans and MRIs often do not necessarily give the clear cut results sometimes published. No doubt the top institutions previously suggested whould have the most up to date equipment available.
Diet and lifestyle changes, exercise, diet and supplements are important. This is an overall thing which can improve general health and assist prognosis, but it's doubtful and not proven that any single supplement will offer a cure.
It's worth reading a good book on the subject:
Lee Nelson M D was diagnosed with high risk cancer some years ago. His book "Prostate Cancer Prevention and Cure" is very comprehensive and covers diagnosis, selecting a doctor, treatment choices, lifestyle changes etc. Although written a few years ago, it's well worth reading.
Dr Charles Myers is a PC expert who has published the book "Beating Prostate Cancer: Hormonal Therapy and Diet".
"Dr Peter Scardino's Prostate Book" is written by one of the top PC surgeons from MSK.
Yes, it's usually worth obtaining another viewpoint: It would be well worthwhile consulting a top medical oncologist who is an expert unbiased consultant.specializing in PC.
Best of luck.