No, I think you misread me. What I am saying is: Lets say you are an engineer in Iran and you work on WMDs and know they are going to be used. Working on them wouldn't be ethical.
I think what I am trying to say is the old 'I have just been following orders' thing. And in a way, because of 'ethical' implications, I believe 'working in and with the system' -and maybe even things such as change control- might have parallels to that idea of 'just following orders'.
As others said, the best thing the engineer could have done (if I understand everything right), is to go public and say: We have this flaw, we need to fix it!
I think the next best thing actually is to not follow change control guidelines - in that way 'orders' - and fix the problem, even though management says that he should bury the data that says that the switch is faulty, and hide from management that you fixed it. Of course, 'next best' could and probably should already be considered as some sort of 'bad'.
I might misunderstand the whole situation though and it what sense the engineers did/didn't make the situation worse.