I saw the entire interview. He displayed a bit of emotion when recalling his experiences of visiting some of the WWII concentration camps. It is quite telling that when Paul Wontorek gave him a chance to express any regret or remorse for some of the things he wrote about, Riedel was unwilling or unable to admit that he'd been unfair to people on certain occasions. Towards the end, he points out his Endora (Bewitched) t shirt he was wearing.
"Noel [Coward] and I were in Paris once. Adjoining rooms, of course. One night, I felt mischievous, so I knocked on Noel's door, and he asked, 'Who is it?' I lowered my voice and said 'Hotel detective. Have you got a gentleman in your room?' He answered, 'Just a minute, I'll ask him.'" (Beatrice Lillie)