For the safari you definitely need a warm jacket, scarf and knitted hat. The wind factor on the morning drive must be taken in to account. You will be given blankets as well by the lodge, but dress warmly in layers so you can take clothes off as it gets warmer.
A jacket with some sort of wind break that is also warm is a good idea for both safari and Cape Town. Honestly you are likely to be more cold in the mornings on safari than in Cape Town.
In Botswana, the lodges will wash your clothes for you (with the exception of your underwear), so you need to keep to the 44 pounds in soft sided bags.
For the men, long cargo pants, a long-sleeved tee shirt, a fleece and then a Gore-Tex windbreaker shell. You’ll also need light hand gloves, and something to cover your ears.
When the sun is up, it may be warm, so off come the layers. And when you’re not in the sun, or at night, you’ll need to add the layers back on.