I have only been to Africa once. I only say that because I don't have a ton of experience. We bumped into a buffalo while stalking a blue wildebeest. I don't think he knew were there, crashed off, and that was that. We spooked a white rhino with the truck, it ran away. There were lions across the river, but we never saw them.
Initially I was kind of excited and scared about DG before going. When I got there, I realized it wasn't that big of a deal.
There are 3 things I have come to understand, from 3rd and 1st person accounts, that are real concerns.
3) Water...nothing good happens there. Hippos and crocs kill a ton of people. Crocs eat you (or parts of you), hippos just as soon kill you for being in their space.
2) Mosquitoes. Deadliest animal in the world.
1) Snakes. This, in my opinion, is definitely something to be mindful of. I personally saw a puff adder from 10' away. Other folks in my party saw black mambas from a similar distance. We spent one sunset walking in knee to thigh high grass and that occupying most of my mental real estate in that moment.
This is what was 10' from us earlier that day: