Boeing is for sure a shit show and terribly managed, but I don’t think they would blatantly kill guys like that. I think it’s far more likely that the first guy did kill himself because he figured everybody would think Boeing whacked him and that would do far more damage to the company than his testimony would. Now any news falls under a suspicious gaze and here we are thinking some other guys unfortunate death is due to nefarious deeds.

Or I’m wrong and Boeing has a CIA division ¯\_(ツ)_/¯