NDAs and injunctions can't stop someone reporting a crime to the police or talking to a lawyer or their MP¹, so anything that claims to do that is unenforceable. How many people actually know that is a different question.
¹funnily enough they don't usually try to do that one, because its generally a good way to get it asked about in the House of Commons, which can be reported with no restrictions at all.
¹funnily enough they don't usually try to do that one, because its generally a good way to get it asked about in the House of Commons, which can be reported with no restrictions at all.