With two Boeing whistleblowers dead in one month, either Boeing is actively killing them, or there are enough whistleblowers that this rate of death is not statistically significant
...and I don't know which possibility is the least worrying
That is true, but let’s not forget big companies have been found guilty (rarely punished) of crimes with no respect for human lives or even rights whatsoever. It isn’t very smart to consider extermination a fact, however it is smart to assume it is a possibility, especially if you are an ethical Boeing employee.