Wikipedia puts the name change at 1971. In what way was the Khmer Rouge not a Communist party? They were literally forcing the entire population onto agricultural communes. One quote from a foreign minister doesn't move the goalpost.
Vietnam didn't ride in to heroically liberate Cambodia from "pretend communists", it was literally in response to military aggression ordered by Pol Pot.
Yikes bud, no need to attack someone who gives zero value to your opinion. Save if for someone who cares.