Could the
Rand Rebellion lead to the South African nationalist party or another popular Afrikaner party which is far left or even communist?[/QUOTE
Well, the National Party were actually pretty to the left in terms of economic policy, and even in the 1970s and 1980s was still fairly suspicious of capitalism.
Here's a nice little counterfactual by an opposition politician in SA in what could have happened if the Nats had gone really hard left.