Just a wonderful set! I admire your pushing to get different perspectives, especially low-down shots. Our first safari involved a stay at Little Governors, too. That was 2010, and I was woefully underprepared with camera equipment. I remember fighting (successfully, I think) the urge to portraitize every animal. But, I will try hard to think more about vertical angle, from your shots.
The 300 seemed to do wonderfully for you. But, I've always wanted zoom for safari--to get the framing better fit to the scene more often. Did you miss that flexibility at all? I even found 300 too short on many occasions, and used digital teleconverter. You? These days, I've been shooting 75-300 (plan to move to the 100-400, for the flexibility, per above), and my wife loves the 40-150 for video. I guess your having both on separate cameras lessens the need a bit for a zoom on the big lens.
Two notes: We were told that the wildebeest initiating the river crossing was essentially random...there is no alpha guiding them. Were you told differently? It is very tempting to just assume the first one is a leader. There's actually psychological literature on that assumption!
I have a different perspective on "lazy" cheetah's. They are really very fragile creatures, in a small and narrowing niche. Just at the edge of disaster, most times, even more, I think, than other top-line predators. Lions, for example, are big and burly, but cheetahs have to hit their prey just right...don't have the option of wrestling them to the ground. If you haven't, you must find the BBC series "The Hunt." You're recognize some of the places they filmed. (We also went to Zambia and Botswana more recently, and I swear we recognized some particular fields they photographed.)
Thanks for your contribution. Inspiring.