As with all international travel, check TIMATIC. There is nothing conflicting at all.

I cut & pasted the testing requirements for the two jurisdictions, but OP should carefully review the entirety of the TIMATIC display because I have presumed that he is a US national and that his departure is from the US. Note that there are also other requirements for the test and that it is equally important to have a printed copy when the law requires one.

1. South Africa:

Passengers entering or transiting through South Africa must
have a medical certificate with a negative Coronavirus
(COVID-19) PCR test result issued at most 72 hours before
departure from the first embarkation point.

2. Botswana

Passengers must have a printed medical certificate with a
negative Coronavirus (COVID-19) PCR test result issued at
most 72 hours before arrival. The certificate must be in
English.