Particularly to your question though, if this is another case of Arkanicide, like a couple of cases that have even occurred recently - the guy who had an accident with a barbell, or the UN investigator, I believe it was, a black gentleman IIRC who washed up on the beach in Florida, then unfortunately let's add it to the list.
Any corroboration from any reputable source would be helpful.
Here you go:
FBI agent brother to cop accused of murder-for-hire plot, dead by suicide: sources