Consider this scenario: if the entire breadth of humanity and its influence were "deleted" from Earth, and then initiated again from the humblest of human beginnings, would determinism dictate that humanity would develop the same way?

The only way human history would develop to the same present is for everything to start over. If humanity were to be deleted and then replaced in the same reality, with nothing changed but for the brief moments of humanity's non-existence, then the factors for human development would, of course, be different from the ones under which humanity originally developed. If all of the factors contributing to the present are not reset along with humanity, the course could not be exactly the same, thus the present could not be exactly the same. My point being, if nothing is changed around the circumstances of human development, human development will not be any different from what it has been to this point. There is no way around determinism. Hope this helps.

Would the Lake Tubo megavolcano erupt 176,000 years after our emergence as a distinct species again? Would our ancestors emigrating into Europe encounter Homo Neanderthalens again (contributing 1-5% of modern Nothern Euro DNA)? If so, would the cycle of ice ages be the same? Would plate tectonics be dialed back to the same point they were at in the evolution from Gondwonaland (sp) to our modern continents? Those things had a big influence on our species' evolution, along with other factors, without which what we were like 250,000 years after we began might be quite different. OTOH it is true that when it's time for something to be invented--because the necessary foundation of technology and understanding exist--it tends to get invented pretty much simultaneously in several places at once. The jet engine during WWII, for example, in America, England, Germany and Italy. So while the details could vary greatly, other things are bound to occur when the ducks are lined up--nuclear power for example.