The guy's full of shit!
With his knowledge and contacts, he could've campaigned and used the law to take down the likes of Bayer, Monsanto, BigPharma, etc.
He, IMO, polluted the world with perversions, couldn't live with himself after a "we've got EVERYTHING on you, flip or we show the world" meeting, and thus bumped himself off knowing that flipping wouldn't stop the truth coming out eventually. So, he left a twisted note hoping (this is how fucking deranged he was) people would see him as a beacon of light for traumatising passers-by.
Nutjob.
Plain & simple.