Our JNB-LVI flight last month on Comair got cancelled a couple of hours before departure and they put us on a Nationwide (SA indie) flight that was leaving an hour later. Their J service was not that bad, but I'm waiting (and fearful that it will be in vain) for the miles to post to my AA account, despite assurances from the Comair person at JNB that they would. We shall see. Our VFA-JNB return flight hasn't posted yet either, nor our JNB-CPT flight, both also on Comair.
Both Zambia and Zimbabwe are eager to sell you visas priced on sliding scales - more for some passports, less for others - we paid USD40 each if memory serves for two-hour transit visas in Zambia (just traveling to the river crossing into Botswana) and USD30 each for 2-day (good for a week I think) single-entry visas into Zimbabwe from Botswana. My understanding is that mutiple-entry visas are more in each country, but probably worth considering if you're intending to fly into VFA and day-trip across the bridge into Zambia while visiting Victoria Falls.