Why wasn´t it recorded?
This is a typical situation where many people, myself included, would say :"There´s obviously a huge plothole going on here, why did they run the risk of having the speech aired live, why didn´t they run a recording?" But it no plothole because, as it seems, this is how it actually happened.
But the questions still stands, why didn´t they first record the speech and afterwards have it broadcast? This is for instance what emperor Hirohito did in the famous speech, where he announced Japan´s surrender. I don´t understand why George VI couldn´t have done the same.