“In no way will China allow that to occur in favor of SK / USA.”
You are probably right, but a NK that wasn’t a constant threat to SK, and removal of the DMZ and all the NK weaponry there would definitely be a positive step. Then it would be for the NK populace to finally figure out that they’ve been screwed by the Kims for almost a century and take “corrective” action. NK needs to have an East Germany “moment.” Say like a day or two shopping in Seoul.
That assumes that whatever currency NK issues has any value at all in SK.