I found this link. I set up an account and entered my vaccine particulars. It approved me and gave me a QR code certificate. It appears to be a standard for African Countries.??
Trusted Vaccines – Africa CDC
A bundle of interdependent packages that aims at digitizing, simplifying, and improving vaccine administration and distribution processes, and the security of port and travel screening activitiesafricacdc.org
I forgot all about that site because at the time they were pushing it for test validations. Seeing how they also do vaccine validations, this seems like the best option since it'd be super shocking that South Africa couldn't read the QR code specific to their system. I had already set up an account thinking I'd need it for my trip last June and logged in and got everything entered and got a provisional certificate. I'll see how long it takes for someone to actually look at my info and give me a good validation but so far it was easy as can be.