All Deaths - that occur in a Province - are required to be Registered in the Province -
Obtaining same - may be a help/
Registration of Death - Long Form Death Certificate - holds all personal information required at the time ** as known to the Informant -[informant may hold back some info ]\
Check with Chief Coroners Office . There may have been an Inquiry -Autopsy - they may be able to search the aprox. timeframe - and hopefully by name.
Now that you have posted - it is still quite possible that there may be someone on this message board - who may be able to assist.
Cheers, Stella