I appreciate that OZ is far far away with a smaller population therefore fewer specialized hospitals. I think I remember that some of the leading Comp. Cancer Centers (CCC) in the U.S. provide for the ability for records to be sent for review. if I were you I'd try that route and seek out a head and neck specialty in a CCC that will review your record.
From here you're on your own as I have heard this ability exists but don't actually know that it as a proven fact.
It is my understanding that the top CCC's are (in random order) M.D. Anderson, Dana-Farber, Sloan-Kettering and the Mayo Clinic. Of course there are quite a few more.
An on line search came up with this: https://www.mskcc.org/experience/be...s/requesting-medical-records-review-mail