Throughout the 1980s, Henderson had been a regular member of the League of Ireland XI squad. When the FAI were asked by the Olympic Council of Ireland to put forward a team to attempt qualification for the 1988 Olympic Games, Henderson would add Olympic caps to his league and U21 honours.
From the 1980s until the 1988 Olympics, Henderson was a regular player on the League of Ireland XI. When the Irish Olympic Committee asked the FAI to form a team for the Games, Henderson added Olympic caps to his existing league and U21 honors.