I'd be intrigued to find out how Ryanair is going to sue Ch4/Dispatches.
They won't sue. Their lawyers will advise against it.
Tough stuff to contest and in the case of the last one, I'd say impossible....
They could always arrange a petition of their staff to show how happy they are working for them. Of course they would probably have to make signing of the petition compulsory under threat of dismissal.