A few things that bother me.
The handwriting expert, said the "N" matched. To me the edge that should have been smooth/strait had a bump in it. To me that would mean someone was trying to write slowly while copying another letter.
His family seemed shady to me. Feels like there is a chance someone was trying to set him up, failed. Then tried again, to make him look guilty.
I'm not saying he is innocent. I do believe he killed his neighbor (accident/self defense idk), but all the crap he has been through could push a innocent person to lose it and do something crazy.
No matter what I do believe the "pussy" with the bodyguard had one of the victims killed to get rid of Bob and the media attention.
And finally the ending "confession". Reminded me of when i was accused of cheating once. I did basically the same thing, even in the bathroom too, except under my breath. "Oh yeah I cheated. I F'd the hell out of her. Totally, I even put it in her a**. You've caught me! Just believe some dude that hates me and wants you."
Anyway I'm not 100% on if he did it or not. Although I believe he did at least the one. The others I feels like it was his brother/family for some reason. Trying to get rid of him. Cause of money/rep IDK.
Whether or not he was innocent. The pressure Bob must have been under for years could have caused him to lose it. Pretending to be a women, cutting up the man. He could have broke and not even realized it.