I’ve used Perl a lot.

> There’s plenty of evidence to the contrary, including Denisovan and Neanderthal that is not present in any African population

OOA does have an explanation for Neanderthal and Denisovan DNA that isn't found in African populations, and that is that the cross-breeding between anatomically modern humans and Neanderthals and Denisovans occurred after modern humans left Africa.

> as well, something like up to 20% of West African genome has an as yet unknown source which is usually referred to as “archaic” or ghost DNA which is not found elsewhere in other populations.

"Archaic" DNA refers to DNA that appears to have originated with some human group other than modern humans and not be shared among modern human populations (the Denisovan and Neanderthal-origin genomes of Eurasian humans would be included here), but specific to some subpopulation. It is not the case that "20% of West African genome" is archaic, though there is a study in which some specific isolated West African subpopulations had archaic fractions that high, which is not something that OOA has no explanation for (the explanation is that those subgroups were isolated from the ones that participated in the various outbound migrations, and so their particular archaic genome is not shared with the groups that migrated out.)

There may be valid challenges to OOA, but those aren't it.

Homo sapiens didn't evolve from Denisovans and Neanderthals. All are branches of human and existed at the same time and interbred.* Homo sapiens survived while Neanderthals and Denisovans became extinct. The majority of the ancestry of living humans, Homo sapiens, was originally from Africa. Europeans have some Neanderthal ancestry (like 2%) due to interbreeding with Neanderthals, but the vast majority of European DNA is from Africa. Sub-Saharan Africans have less Neanderthal ancestry than Europeans and more Homo sapiens ancestry.

* https://en.m.wikipedia.org/wiki/Interbreeding_between_archai...