OP, a lot of your posts sound incredibly naive. Lots of people, when they leave jobs, sign contracts which agree they cannot talk about what happened before they left the job. If they are lucky, there is a bit of a pay off. These are legally binding documents, and if you break them, there can be legal consequences. In general, the employer has a lot more money than you (doubly so, if it's a royal household, I'm sure) and so can take you to court.
There are situations where the press can report on these things, but for someone who's signed this sort of agreement to come out and do a "tell all" would put them at a lot of personal risk. In general, the police do not get involved in employment disputes, and wouldn't be interested, either.
I suspect a lot of what we see in the press doesn't come from the parties involved, but from colleagues/ex colleagues who know the person involved won't ever be able to reply.
And yes, I'm sure that Charles/William/Andrew etc are all shit employers too. Charles was well known to be a dick to his tenants when he was duke of cornwall. So part of it is also what the national press are interested in reporting.
But I think the idea that we should automatically take the side of the (powerful, wealthy) employer, over their employees because those employees aren't willing to speak out is a pretty dangerous one.