Hey!
If it helps, I flew SAA from CPT to Mauritiur, via JNB.
I've got to tell you that you will have to "breath and be pattient" with SAA non reving system.

I listed on the flights I wanted to fly before leaving Europe over the phone, calling to Germany. Everything was fine.
Then when we arrived at the airport (CPT), I went to the economy check-in, and they didnt even look at my reservation, they told me to come back 45 minuts before flight departs, because I would be called by them. I told the agent: how are you going to know who I am, and If I am here at the airport? you didnt even look at my reservation or typed anything!!! He just told me, I will call you, stay in that corner, and I will call you back.
So we did.
30minuts before departure, they made a final announcement calling all pax to check-in because the flight was closing (I was amazed by the laaaarrrge number of people who was still going around without checking-in...........30 minuts before departure!!!!!!!!!!!!!!!!!!
We approached, and an agent took our paper ZEDs and checked us. I gave him my flight listing, which he absolutely ignored. I knew it because he did a mistake at my name at the boarding pass. I supposed he checked us like a passenger who has no reservation.
The good part was he confirmed us straight to Mauritius... so we didnt have to standby again at JNB.
Maybe he thought we were regular passengers... who knows!

The craziest way of dealing with a non revenue system I have never experienced!

I forgot everything when the captain literally said over the microphone: Ladies and gentelmen, wellcome onboard of this South African Airlines flight to PARADISE!
So be patient, South Africa is an special country, which I was absolutely impressed, mostly because of their way of living and doing things.

hope it helps.