Beetle, no that reference is definitely a mistake. He had nothing to do with Northern Ireland other than the lead the Irish team to play against them in Belfast. There is often confusion in some circles. Republic of Ireland, Northern Ireland, Eire, Ulster etc. Confusion reigns.
Believe me I know. He's part of the folklore here now. It took an Englishman to restore pride in the Irish football team. As a kid I followed England and couldn't even name a member of the Irish team. But I could name the entire England '66 squad. It was ironic that part of that squad led the Republic to victory against England on one occasion.