This is hardly news. The origin locale and timeframe (acquired zoonotically from Chimpanzees north of Kinshasa, probably around 1908, travelling by river to Kinshasa and Brazzaville, where social conditions permitted amplification and adaptation to human hosts) have been strongly supported by evidence for about a decade. David Quammen discusses it in detail in his book "Spillover". While this study adds more evidence supporting the theory, that area and timeframe was pretty much accepted as fact in the research community for some time.