I don't see the connection. If he was an active member of the JW's that would be one thing, but saying he was raised a JW would mean that everyone here on this website is mentally deranged and a potential murderer because most of them were raised JW's or are ex-JW's.
If he had been raised a Catholic or raised a Jew what would that have to do with anything? Especially, if that person isn't connected to that faith anymore. Aside from being interesting it's meaningless. The guy obviously was mentally ill. Mental illness attacks everyone from every sector.
Humans are humans with human failings, and sometimes we connect dots where there is no connection.