I don't see why not. Just because you might think the exposure would be benign, doesn't mean he would agree. A person's private life is just that--private. I'd sue in a heartbeat if a major secret of mine were broadcast live on the radio the way they did with this guy. How humiliating. This sort of thing is probably excusable when done to a public figure, but not when done to some average joe.
Are you saying that someone can be sued for reporting the truth? If courts, juries and judges accept this, our system is done for.