From the source BBC article it says:" Boeing said it was saddened to hear of Mr Barnett's passing. The Charleston County coroner confirmed his death to the BBC on Monday. It said the 62-year-old had died from a "self-inflicted" wound on 9 March and police were investigating. "

I say the latter is a EXTREMELY SUSPICIOUS statement from either the big corporation Boeing, or the corner being bribed by Boeing. Due to Boeing making that statement, I would immediately suspect of Boeing's big corporate top brass of actually hiring hitman to assisinate this whistleblower from testifying further, all in the name of continuing profits and keelping good corporate reputation. Most importantly. it does not make sense for a 62 year old senior enjoying his golden years and pensions and retirement to suddenly commit suicide in the midst of a heated legal battle and whistle-blowing, especially when he thinks he stand for justice, and need to divulge further truth to prevent Boeing Big Corporate bigwigs from further harming American and Global Societies.

So the ongoing investigations is well warranted; but unfortunately: greedy corrupt enforcement can be easily bribed.

Then in the worst hypothetical cases, possible results for disgruntled family members is to "take the law into their own hands", "eye for eye/ blood for blood" or "start a new rebellion or political movement".