Not really harsh.....may well be accurate.
I did notice the head dip then 'stumble'.
Could have been something neurological, which a necrospy probably would not detect, or he just lost his balance.
Amazing that you caught it on camera!
Tho disturbing for you to watch.
Sure helped solve what would have been a mystery.
I don't think changing the roosts are in order,
it was a just a freak accident.
Sorry for your loss. :(
Do let us know what you find.
Curious if there will be anything...