If you look at this clip you can see the same people minus their jackets after the lights got to them.
https://www.youtube.com/watch?v=nP-rgKUzsUI
The clip seems to show a rehearsal with a director with a baton leading the actors. He is leading other actors with no camera to be seen on them. Accounts agree with the director being in the studio. I guess I should get a baton when I am directing.
The guy with the headsets can be seen adjusting a camera lens at :18sec. "Pan left...no, your other left". I suspect he is on headsets to someone telling him about camera adjustments. More staff are in the studio now. The tall candle on the table has vanished. The bottle moved. Typical rehearsal. And I think the director is wearing tv makeup in the clip. Dark lips typical of the era. I think this is staged for a newsreel clip and photos and not from the actual broadcast.
Here is a page on the ETF website about the production;
http://www.earlytelevision.org/queens_messenger.html