I think we can know this counterfactual. On bad science fiction shows like Sliders, they visit "parallel universes" where just one or two things are changed from our world.
In one episode, they finally believe themselves to be "home". Until, late in the episode, one of them notices that the Golden Gate Bridge is blue. Supposedly, nothing else is even slightly different than the one they are from.
Well, if we examine that premise, it's pretty dumb. At some point in the 1930s when it was built, someone had to source the paint for the damned thing. The plant that made the paint, even if it was the same one, used different pigments. Mined somewhere other than where they found the raw materials for whatever color of orange the bridge really is. Each of these slight changes, 70 years before the protagonists showed up, would have caused even bigger changes. Trucks taking different routes, causing different traffic patterns, different delays. Suddenly, people are being conceived 5 minutes earlier, or 5 minutes later (or not at all). It's doubtful that anyone born after whenever the divergence occurred (whenever that was) is genetically identical. Doubtful that anyone born even half a generation later has the same birth name.
Pretty safe to say if the dinosaurs weren't godbombed, there wouldn't be humans. The number of magical convergences is too high, even for a shorter period of time.