Mafia 84. Memorized it, turned it in, forgot it!

I don't understand the point... why is it so important not to reveal the role of an already eliminated military officer?

And what's the difference between being dismissed and being killed anyway?

The military officer doesn't die when dismissed; he's blocked, just like with a regular block. Therefore, it's in everyone's best interest to eliminate the military officer as soon as possible.

The scholar can save someone from being dismissed. He can't save them from being killed.
So, for the students, there's no real difference – both actions remove them from the game. But at least in the newspaper, you can distinguish which action was performed by the mafia and which by the military officer.