Here's what I do in Africa. First off, my "Outfitter", who actually owns the ranch, will not accept tips. That may or may not be standard. I have asked and he says that since he is the owner, it ain't done.
I seek his advice on tipping and he adds it right to my bill. The exception I make is that, since I know my tracker personally now, and the camp manager/chef, I tip them in cash. And...I tip them more than the outfitter says is standard. If I have a PH with me, I also tip him seperately, but most times, I am alone, or with a tracker.
Too Short