The Fox show went into damage control Wednesday, with Cowell _ known for his acerbic comments _ and a series producer denying that he had heard what Richardson said.
Instead, he was talking to Abdul about Richardson's contention that he deliberately sang "Mayberry" in a nasal tone, Cowell told "American Idol" host Ryan Seacrest on Seacrest's radio show Wednesday.
"I was saying to Paula, `What does he mean, he sang nasally on purpose? I didn't understand what he was saying.' So I hadn't even heard what he did. Then my eye rolled, given what I was saying to Paula," Cowell told Seacrest.
"I've never heard so much rubbish," added Cowell, a British record company executive.
On Wednesday night's show, Cowell stood firm.
"I didn't hear what Chris was saying," he said. "I may not be the nicest person in the world, but I would never, ever, ever disrespect those families or those victims. And I felt it was important to set the record straight."