Complex sentence: Susanna Hoffs has verbally confirmed that she once turned up for recording in the nude, having been jokingly told by the producer that Olivia Newton John, whom he had recently worked with, had found she recorded her best take nude.
Split into simpler sentences: Susanna Hoffs has verbally confirmed the rumor that she once turned up for recording in the nude. She had been jokingly told by the producer that Olivia Newton John, whom he had recently worked with, had found she recorded her best take nude.