INTENTIONAL HARM BY PUBLIC SHAMING
The video did NOT have to be aired. But it was and it was done intentionally to cause harm through public shaming.
Certainly the video was not aired to benefit the woman in question but rather her indiscretion was used to benefit the production.
She should be at least paid for the use of that video.
I don;t know what lible law is in the UK but in the States libel is based on intent to do harm.