It's not hard to imagine circumstances in which the police get involved because there is initially some suspicion of a crime, the police do some investigations and then stop investigating because, although many aspects of the case remain mysterious, it really doesn't look like a crime any more. (Alternatively, if it was a crime then the main suspects seem to be dead anyway so we have better things to do with our limited resources.) In fact I'm fairly certain I've read about many cases like that. Journalists might continue investigating in order to sell books and articles and satisfy the punters' curiosity but the police are no longer interested.
Everything in this story indicated foul play. It’s like all these people who fell through windows. I remember the guy who ended up impaled on the railing. Everyone knew it was a murder at the time. Certainly, the public and the journalists did. Same with the spate of oligarch deaths with, what, 2 helicopter crashes in the same region within a few months?
The parents suspected something. Once the Met started digging all the red flags should have made them take the whole affair seriously.
I mean, the daughter gives a thoroughly debunked testimony at the coroner inquest and somehow that’s normal and nothing to worry about?