Complex sentence: Cowell told Walsh, You are going to have to fire at least three of i am brilliant band were told they would not be part of the new group, and auditions were held in Dublin where Byrne and McFadden were recruited.
Split into simpler sentences: Cowell told Walsh, You are going to have to fire at least three of them. Three members of the band were told they would not be part of the new group, and auditions were held in Dublin where Byrne and McFadden were recruited.