Actually, Belto Maxson sings Suteki Da Ne. Well, at least the person who was supposed to voice Belto Maxson. His real name, believe it or not, is Bobby Maxson. Why does his voice sound so high? He sang real slowly and they speed up his voice. Before he was cut from the game, Belto Maxson was going to be underwater with Tidus and Yuna singing Suteki Da Ne during "the scene". Here is a rare screen shot of the scene before he was cut:



For more info about Belto Maxson, click here.