If someone sees what he deems do be immoral, unjust or otherwise illicit or repugnant behavior especially in an organization he's intimately familiar with and blows the whistle, is his "snitching" usually morally justified?
Maybe. This is sort of a case-by-case thing. Never if it results in giving classified information to our enemies. Always if it exposes illegal activities. If these conflict, I'd let a judge and jury decide.
Not unless actual harm is being done to people through violating their rights.
Depends. Some people are busy bodies or blow things way out of proportion. Some might have contributed in said behavior but are coming out now in retaliation for something
He's not a snitch for doing that
I don't think it's "snitching" in that case.
Unless he does it for personal gain and is convinced to uncover an evil, he's justified and shouldn't be seen as snitch or traitor.
Replace "and" with "then if he truly" for it to make sense.
As do I