You would have to ask them.
At a guess I'd say it's an attempt to distance themselves from it, just in case it does come back to bite them. I don't know how successful a strategy that is though. 'Repeating a libel' is most definitely actionable.
I know of what I speak, by the way - I am a journo (a properly trained one, unlike most of the hacks in Fleet Street), and I've passed the course on newspaper law.
