Well, if we each get a chance, I would take the first crack.
It means that you have to read their mind. That's why it's an inherent wild card. It's very vulnerable to subjective judgments. You need to have objective standards for these rights. Good faith leaves it all up to non-objective considerations.
Frankly, whistle-blowers are exposing the truth about abuses of power that betray the public. Does it really matter why they are exposing the truth? They're witnesses for the public interest.
In the United States, some of the most significant witnesses in history were mafia hit men. They weren't testifying and exposing crimes because of their values. They were doing it for self-interest, but we needed their testimony, so we guarded their lives whether or not we thought they were good-faith human beings.