they did not export capital by keeping countries from industrializing, nor did they have a financial oligarchy like imperial core countries.

Disagree. They definitely did repress the Soviet block counties for their own good. And they definitely had an oligarchy, though it wasn't as straightforwardly financial.

But it sounds like you're using definitions that try to exclude countries that are nominally communist from terms like imperialist, so I can't really do much to argue with your definitions. I'd just say that your definitions aren't what I use or what are commonly used.