Nothing so far can prove anything. Where Wint is concerned, despite his being charged, we can't say his DNA is proof he committed any crime unless eating pizza is a crime. Right now, that DNA is only circumstantial evidence that could go to show that Wint was with the family and Veralicia Figeroa while it is suspected they were held captive. The lab could have mixed up samples. Police could be framing him. He could have walked by the house, wearing latex gloves for a legitimate reason, spotted the pizza, had a slice, thrown it back in the box and....So forth so on. We are not a jury who will decide if this or any other evidence turned up is compelling enough to meet the legal standard a judge will instruct us on. If there's ever a trial, it won't put debate and speculation to rest.
Along with you, I wonder "what new revelations will be coming next and when?" !
All of us want to see justice done. But the first amendment assures us that we have a right to argue our viewpoint on a case online and off, no matter how flawed or limited our view might be. In the back and forth, often when those viewpoints are opposing, we gain more insight, are challenged to think more critically.