What they are not bothering to mention is that we use virus to target specific cells for gene therapy. That virus commonly bring DNA from foreign hosts across species all the time. That an ERV is a foreign invader to begin with, that all the shared markers are from ERV sites.
No one is certainly denying that after infection, the body incorporates the foreign DNA to use in protein manufacture, and is THEN passed to future generations vertically.
There would be divergences whether they shared ancestry or whether it came from foreign infection. All the divergence can do is tell you when the foreign infection occurred, not if they share a common ancestor. And this is based solely upon mutation rates, while ignoring the more fundamental truth.
https://www.ncbi.nlm.nih.gov/pubmed/28568290
"Hybridization increased additive genetic and environmental variances, increased heritabilities to a moderate extent, and generally strengthened phenotypic and genetic correlations. New additive genetic variance introduced by hybridization is estimated to be two to three orders of magnitude greater than that introduced by mutation."
So simple mating between different humans would have affected the appearance of time by two to three orders of magnitude greater than mutation alone. The same with apes. Therefore the actual infection time would be much, much closer in the past than they account for, being they neglect the changes due to mating which has a 2 to 3 times greater magnitude of producing changes.
I understand how they come to their incorrect conclusions of time, they ignore what is two to three times greater in magnitude.