This doesn't even make sense... First you bring up
phenotype range and now you're bringing up admixture in groups bordering Sudan. Phenotypic range in an area=/=admixture. If that was the case then it would ring true for Nigeria who Southern Nigerians with a long history with Fulanis still do not have any Western Atlantic/Berber admixture. And admixture=/=phenotype. And
most of the admixture you listed for East Africa was not recent but during prehistoric times when there wasn't even much phenotypic diversity. This is especially true for the Nilo-Saharan speakers.
MORE importantly the admixture grapth you posted does not address the group of West Africans I was talking about who were INTERMEDIATE between North and Southern West Africa.
THIS is what I am talking about...
52,4% of mtDNA H in Mali, 22,5% in Burkina Faso. That clear signs of different groups coming in even ancestry from outside Africa. This is from the intermediate groups I was talking about that surround Mali like Niger, Senegal and Burkina Faso.