I don't know about that. History teacher Adrian Targett can trace his roots in England back 9,000 years.
In any event, the English were a tribe in northern Germany, the "Angles", as were the Saxons. The Angles were looking for good farmland, and started a movement of their people to Britain, and took land by force. This started in the late 400s and early 500s, when the Romans had buggered out and there was no effective government or military to defend the Isle. After a while, the original natives were driven out or absorbed, and the part of Britain where the Angles were concentrated came to be known as "Angle-land", i.e., England.
So, this road was built in a part of the Island of Britain which later became England, but it did not help assimilate the English to Roman rule. It may have helped the Celtic tribes in that part of Britain.
That was an mtDNA study. Even assuming the results of such studies are valid (and I don't), Targett and the cave man remains could have a common female ancestor. The Angles, Saxons, and Jutes weren't even in Germany 9000 years ago.