Complex sentence: Roddy was actually the producers' second choice to replace Olson-their first choice, Hilton, was instead committed to hosting a game show called "Bamboozle", which did not pass the pilot stage.
Split into simpler sentences: Roddy was actually the producers' second choice to replace Olson. Their first choice, Hilton, was instead committed to hosting a game show called "Bamboozle", which did not pass the pilot stage.