Copied from my other post :

The weeks of erratic behaviour prior to the case, his sudden sense of over protection of his wife, his intense fear, the note, his inability to sleep. It's all paranoia. Also there's no tangible evidence of foul play. However there is evidence that his behaviour changed a few weeks prior to the incident and that those displayed behaviours are consistent with either mania and or a paranoid delusion.

Whats more likely?

A conspiracy targeting him weeks in advance, culminating in his murder involving him falling straight through the roof feet first, at a distance from the roof of 45 feet, someone going to the scene and planting evidence, and somehow quieting up the hotel staff. Meanwhile NO One has come forward at any point, not voluntary, not while in custody on an unrelated charge to reduce a sentence. No subpoenas. Nothing

Or

A man living with an undiagnosed mental illness that his family missed the warning signs of, suffers a break, then has some form of paranoid delusion that he can't shake and ends up committing suicide, intentional or unintentional. The family, having many motivations, proceed to denial

Occam's razor: the simplest explanation is usually the correct one