What about a bean-bag support?
On a guided safari you won’t be let out of the vehicle at any time. So arguably more useful than a tripod is a basic bean-bag support. These can travel with you completely empty; all you have to do is find some rice, or sand, and it becomes a handy support for your camera’s long lens.
These are practical for general wildlife photography, but if you’re on a self-drive safari, getting out of your car is not only potentially dangerous, but also counterproductive because animals will notice you immediately and scarper.
Instead, treat your car like bird hide by winding down the window and rest your lens on a U-shaped bean-bag like the Stealth Gear Ultimate Freedom Double Foxor the Grappler, which both hook over a car door. A more lo-fi approach is to turn your wound-down window into a safe-zone for your camera by adapting a simple swimming pool noodle to fit over it.
If you’ve got a few walking safaris planned, consider a harness or sling like the Joby UltraFit Sling Strap or Lowepro Topload Chest Harness, which can make a quick-draw easier.