I didn't think it was so much Zeon Deikunbeing crazy as much as it is overworked.he probably died of natural causes.
As for Zeon name change? They didnt. It always went with the flow it had in Origin. It always went from Mundo to Republic of Zeon after his death, to Principality of Zeon during the war
Oh so they didn't retcon away Republic of Zeon? I thought that's what happened.