I did a thread on this back in 2013, when bbc put an actor in a doc, and said he was a soldier in northern ireland, when i stated he looked like a quite well known actor.
https://forum.davidicke.com/showthread.php?t=261881
So it seems, the bbc does it alot. I never watch the bbc, as i worked for the scum back in 90's, and know what they are like. But i saw, the above show on the net back in 2013, and assumed, one of the pretend soldiers, was infact an actor.
So although i never saw your newsnight clip, i assume using actors on shows, and docs, and news, is a common trick used.
Unless someone pushes further, and goes and investigates more, probably generally these docs, and such, just get accepted by the majority.
Just look how many docs were on uk tv, about socalled potential trouble in russia during world cup. The world cup came about, and the russians were very well behaved. The russians these doc makers filmed, said they were set up to make it seem russians were looking for trouble, and were sickened by how they were used by uk tv shows, to portray russia as a violent place during the world cup.
We know from history now, that russians never were anything like they were portrayed on uk tv, trying to frighten the public in uk.
So companies like the bbc, misrepresent enormously, and are just there for propaganda, in terms of there docs, and news time specials.
Just look at how they misrepresented the syrian boy earlier this year, and when that syrian boy was brought to west by russia, teh western news agencies, did not want to know, about the truth, on how that boy and family was duped by western news agencies.