The Las Vegas outfit Ties is wearing is fun--quite a statement! One does get tired of seeing black or white shirts all the time onstage... I guess it's in keeping with the Pop/satiric slant of the music.
I really don't think it's him performing. The recording is the standard one that comes when you order the score, and he breathes in a few places when he's playing, and his fingerings are really strange. Regardless, it's an incredible piece, and amazingly fun to work on. Ter Veldhuis is a brilliant composer.