Complex sentence: Rob LaBelle, who was a close friend of Biller, was cast as an unnamed Talaxian prisoner but he concealed the connection during his audition to avoid preferential treatment.
Split into simpler sentences: Rob LaBelle, who was a close friend with Biller, was cast as an unnamed Talaxian prisoner. LaBelle's friendship with Biller did not influence his casting, as LaBelle concealed the connection during his audition to avoid preferential treatment.