Misty, MAD is still fact. Russia would just be enjoying the spectacle of N Korea causing the US angst. They are not going to actually go to war for them. China doesn't care for them either. They are fed up with starving refugees flooding across the border.
Nobody is going to go to war for them. Besides, they wouldn't last long enough for the Chinese cavalry to arrive. It will be Desert Storm II without the luxury of having a desert to fight in. The yanks are not going to allow it to be fought in the South and conventional forces will not be able to prevent that.
I doubt that China will just let the west take control of North Korean.
