I don't really have an opinion on this either way, but I would just like to point out that it is in fact possible to say publicly (or privately for that matter) that you will not kill yourself and then kill yourself. There is no fundamental law of nature that says if you say something that are cosmically stuck to that statement.
i literally know absolutely nothing about boeing or this guy. i have 0 opinion on this case at all. what i have an opinion about is people using someone claiming they won't commit suicide as evidence that they were murdered when they die. see john mcafee. it was a major headline when he died that he said he wouldn't commit suicide and then he died therefore conspiracy. except in reality he is the exact sort of unhinged maniac that would commit suicide. i wouldn't be surprised if there was ACTUAL evidence of a conspiracy, but him saying him saying he won't kill himself aint it.