While I feel that these 'secrets' should be exposed to the fullest extend, I cannot help but think that any pursuit of ALL Apartheid protagonists, be it their corruption or 'crimes against humanity' would simply cost too much. By cost, I mean financial as well as social and National
Yes, dig deeper into the families of the Apartheid demagogues (as a start), then into the businessmen and the companies of the time. If GLARING, undeniable criminal benefit is exposed, demand reparations or compensation. Pick the low hanging fruit, and make sure it benefits the victims. The cost will still be VERY high but if it is cathartic and will serve a defined, FINITE purpose, do it.
Having said that, to hold average white South Africans accountable IN PERPETUITY for Apartheid - based on these 'secrets' will most certainly be terminally unproductive. While the scenarios are vastly different, IMO, it would be the same as the Jewish folk holding today's Germany accountable for the Holocaust - forever.