There is more than 1 fraternity death per year.
Here is a bloomberg article…
You can’t compare 58 per 100,000 deaths with fraternity deaths to get good numbers. 58 deaths per 100,000 are deaths from all accidental causes. I am assuming the 58 per 100,000 number is correct.
http://www.bloomberg.com/infographics/2013-12-30/sigma-alpha-epsilon-deaths-most-among-frats.html