I know not much at all about South Africa but what you describe puts me in mind of https://en.wikipedia.org/wiki/Newcomb's_paradox - the world will be better off if powerful criminals believe that they can give up their power and still live consequence-free. Then at least they have the option of giving up power and everyone might benefit.

If they think they'll be given the Gaddafi treatment [0] then the rational thing for powerful monsters to do is go down swinging.

It is better to have systems to punish crimes, but it is also important to have meaningful amnesty even at the expense of fairness.

[0] https://en.wikipedia.org/wiki/Disarmament_of_Libya