ESPN had 4.78 million bracket entries and just under 43% of them had the Kansas Jayhawks to win it all. Also bowing out early have been #2 Villanova and a pair of #3 seeds in Georgetown and Pittsburgh leaving no perfect brackets at ESPN and out of the close to 5 million entries, there are only a total of four who have 15 of the 16 remaining teams.
However, the incredibly rare statistical occurrence of Herrmann's bracket has been questioned. CBSSports had no record of the bracket since it doesn't track the brackets submitted to their Bracket Manager program and also it does appear to let players change their picks after the start of the tournament to some degree. However, Herrmann's mother said he didn't cheat so that's good enough for me.
The bracket can be seen below by clicking on the thumbnail below:


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