Parents all too frequently have a poor understanding of their children's mental health. The opinions of close friends is a better assessment of state-of-mind.

I have no idea how much any of this applies to the case being discussed here. I doubt other commenters have any better idea and their assessment comes down to their own biases.

Be wary of statistical claims when something 'seems to be happening a lot'. Something not happening is generally not news, so you lose a sense of what proportion of a population you are considering.

Even if you know that 30% of deaths of whistleblowers were murders, that means that for any given death the likelihood is that it was not murder.

Every case deserves to, and should, be investigated thoroughly.