I would guess that the real answer is Jamie's old nightmare, Rights Management.
In the UK the BBC is quite privileged, it has a blanket UK broadcast license for most music and it has years of archive footage for which it either owns all the UK rights, or it at least has a paper trail indicating who needs to be paid. A lot of organisations were willing to do a deal with the BBC inside the UK because it's a public service broadcaster. BBCA isn't a public service, it's just another for-profit, so everyone wants their slice of the pie. That starts with the host, the captains and their guest panelists. Then you've got music videos shown in some rounds, archive footage, excerpts from musical recordings, and so on. It's almost the worst show you could conceive from the point of view of rights problems.
Just watched NmtB for the first time. I don't actually watch television over here (.de). But I'm so awestruck I'm seriously considering moving over to the UK and buying a TV set there! Dude, this on public television! Awesome!
OK. Sorry about that. I was mistaken. It's actually in London. I should more read more carefully. But there's apparently a video from Louvain floating around as well.
Me: That is truly the pinnacle of Donnie Osmond's career. They: Are you sure? Me: When's the last time you said, "That's an awesome thing that Donnie Osmond just did there"? They: Point.