"Why do the member’s of South Africa‘s parliament think the results will be any different this time?"
The parliament doesn't think the results will be any different. The leadership/parliament will get rich by looting the people, the people will starve. The leadership will milk it till there's a revolution, which may not be for decades, and escape with the loot if ever necessary.
People get the government they deserve.
Even many blacks, after a year of "Saint Nelson", wanted Apartheid and white rule back.