[Niamh.]

Braden and Rusticgal, my theory on it is :

Spoiler:

he was murdered, firstly the call he got that made him leave his house (never to be seen alive again) came from inside his work office which was next door to the building where he was found dead. If he got a call from work that made him leave then logically he was rushing to work because someone asked him to meet them there. I think he must have had some information of maybe dodgy dealings going on there and someone (maybe his friend Porter) wasn't happy and wanted to shut him up (odd that Porter got lawyers involved, refused to help the Police involving his bloody best friend's possible murder and got a gagging order on his employees) I think maybe he was killed (or seriously injured and incapacitated) by a blow to the head (he had skull fractures in the autopsy) and maybe whoever did it dragged him to that roof (which might have caused those unusual injuries to his tibia) and pushed him threw that hole in the roof hoping that it would look like he committed suicide

PS. Braden he had absolutely no history of mental health issues though so a psychotic episode would be a reach I think