Lack of evidence is not evidence for something else. Your claim doesn’t become true, if other claim is not proven correct.
He gave you examples of evidence for his claims. You have not been able to provide any evidence for yours. If of two concepts one concept is supported by evidence and the other is not which one is more reasonable to accept?
I am not sure if I understand correctly what you try to say, but if the point is that humans have same retroviruses as some animals, it is not a proof for common ancestor. The same way as the “common ancestor” got it, could have happened to many species, by similar way, without there being common ancestor.
You mean some other animals. People are animals too. And it is not "proof" it is evidence. You clearly do not understand the concept of evidence. And if you want to claim some other method, guess what? The burden of proof is upon you.
Fingerprints are not proof that person commit the crime.
But once again, they are evidence.
In the sciences one works with testable ideas. The tests provide evidence. If an idea fails a test that is very strong evidence that the concept is wrong. If it passes the test that is evidence for the concept. Thermos asked you if the fingerprints were evidence that the person was at the crime scene. The proper answer would have been "Yes". No one asked if it proved that the person did it. In fact in criminal trials there is no ultimate "proof". There is only "proof beyond a reasonable doubt". If you ever thought that someone was "proved" to be guilty of a crime then by those same standards you should accept the theory of evolution. It has as much evidence behind it as any murder trial.
A discussion on the nature of evidence would help you.