The diver I'm told may have passed away so it is a case of finding family members or other sources he told about the incident.
However, based on known -if rarely studied- sea creatures I believe that I may have identified the shark killer.
So what was it?
The answer to what it, and some other previous unknowns are can be found in my last book (two formats exist).
I am a tease.
Despite what it says on the site you order the books via your nearest printer NOT the United States -you'll see postage for your area appear once the book is in checkout.