The change from Cro to Homo sapiens is not an example of speciation. Cro is a completely modern human. Our ancestors some 100,000-160,000 years ago are called archaic humans, but they are extremely close and do not represent speciation either.
You apparently are doing the microevolution vs. macroevolution dichotomy. Its not a dichotomy at all. Its a matter of degree. From one generation to the next, differences develop in a population that is isolated. Over time these differences can add up. This is especially true with selection pressure and with complete isolation. But evolution does not require speciation. It requires change from one generation to the next.
No theory in science has ever been proved, nor can one be--by definition. They can be disproved.
But theories can only be considered theories when they have withstood a number of tests and been confirmed at each test.
The theory of evolution has withstood 150 years of testing. There were virtually no hominid fossils extant when Darwin published in 1859. The hominid fossils have confirmed, rather than disproved, the theory ever since. And, there are a lot of species going back millions of years, that appear to have evolved one into the other. At present there is no scientific evidence that this is not the case (religious belief, or rather disbelief, does not constitute scientific evidence).
The new field of genetics could have disproved the theory also, but it only supported it.
In all of these cases, the new data has supported the theory of evolution.