Hey I got busy over the past couple of days but wanted to come back to this

it also seems they're playing the long game and that the world, and the future possibility of leftist movements, would be much worse off if China were to cease to exist.

That is a valid point, for now at least. No matter the objectives, weakening the US empire is a good thing. But at this point I guess we can't really predict whether or not they will save the world and usher in a socialist utopia if they establish themselves as the primary global superpower, or if they'll just end up perpetuating imperialist projects but maybe they are a little nicer to the indigenous people that they are extracting resources from.

As for the Cambodia thing you are right and that would be better question for my Maoist comrades lol

Here are some links about mining in Africa that I just found, I don't remember what I read specifically when I learned about it

South China Morning Post - Science drives China's Westward expansion in Africa

The Hindu - Africa is challenging China's mining hegemony

EE Times - China's Footprint Across Africa Beyond the DRC