DL has a discounted rate thru AfricaAlbidaTourism.com for Vic Falls Safari Lodge and Ngoma Lodge, Botswana. Maybe other airlines have similar?
Anyway, I'm exploring ezeds etc (from JNB--a task to return as upgraded!).
I found this on SAA rev site:
Air transportation charges
Base Fare 51.00 USD
Fuel surcharge (YR) 184.00 USD
Total Air transportation charges 235.00 USD
Taxes, fees and charges
South Africa: Passenger Safety Charge (EV) 1.25 USD
South Africa: Passenger Service Charge (ZA) 23.03 USD
South Africa: Passenger Service and Security Tax (UM) 1.60 USD
South Africa: Air Passenger Tax (WC) 12.64 USD
Zimbabwe: Aviation Infrastrutural development Fund Levy Fee (XI) 15.00 USD
Zimbabwe: Passenger Service Charge (C 35.00 USD
Total Taxes, fees and charges 88.52 USD
323.52 USD
x 2 adult(s) = 647.04 USD

Certainly a bit lopsided pricing, eh?
ezeds (always iffy for major tourist destination) are about $300 less. Hardly worth the anxiety--$75pp each way. Rev is the best choice for limited time frame, too.
We're getting price quotes from Albida shortly--more when I receive pkg details and $.