The Corner special event consists of more than one part. An example of a corner event is “A well placed corner kick from Matt Mattson was followed by Jack Jackson’s hard but accurate header”. It's not known how a corner is triggered; the rules don’t mention it and there has never been any pattern noticed as to how they happen. However once a corner is triggered it consists of two parts. First your set piece taker must have sufficient set pieces to take a “good” kick, and then the receiving player must have sufficient scoring to put the ball in the net, just like with Technical and Winger events. However the number of Head specialists also indirectly figures into the equation here. The rules state: The higher the number of Head specialists in your team, and the lower the number of Head specialists among your opponents, the better your chances to score. Having no Head specialists at all will make you very weak at defending against corners and very weak at scoring on your own corners. So while it does not matter if the player scoring on a corner has head or not, the number of head specialists on your team and the opposing team modifies your overall chance of a successful corner.
based on an article by Elgard