You are pushing uphill. The "data" doesn't say what you think it says.
The "YES" vote was 61.6% - That is 61.6% of the 79.5% of eligible Australians who participated = a "YES" vote of 48.65% of the total eligible population, which means only just over 5% of the non-participants would have needed to vote "YES" to carry this as a compulsory referendum where every eligible person actually voted.
Here is the breakdown of participation by age group and sex:
Look closely at the age groups that did not reach 80% participation. Do you really think those people would have voted unanimously against marriage equality? That would be the only way a compulsory referendum would not have passed. Give up mate.
