One issue that I've seen raised before is that there's a bit of a Catch-22 in public perception in Africa. As you point out, withholding the experimental drug has nasty overtones of "saving the cure for the white folks". But there's also a real risk that if they gave the first experimental treatment to Dr. Khan, the narrative would be "using the black folks as guinea pigs". Both of these concerns are based on actual history, so they're not easily dismissed in the region.

I don't know how you balance that. If the treatment is new enough, you really might not know whether it would help or hurt the patient's odds of survival.