There really is only one person that can prove that Rich was the leaker of the info - Assange. If he were to prove it, the whole Russia conspiracy thing and the reasons for the unmasking - go down the drain. It will destroy the Dems. They can't allow that to happen. They will go to any means to stop it. I think Assange had better start to rethink his non disclosure policy in this case. After all, the leaker is dead so no harm will come to him. The only harm now is to Assange. He is the loose thread. Right now he has the protection of the Ecuadoran embassy. The reason he got the protection was the fake charges against him for rape in Sweden. Sweden has now dropped the case. The only thing keeping him in the embassy is an arrest warrant the British have on him for not obeying a court order. If the British drop that, the embassy has no more reason to offer protection. They may say to him - goodbye. Now he has no protection and is out in public - a target. The only way to make himself less of a target is to release all the info now. Once it is out there, with a videotaped deposition - there would be no need to knock him off. It wouldn't accomplish anything.
“...Assange had better start to rethink his non disclosure policy...”
This is my exact conclusion as well. Now is the time for Assange to announce the truth of the matter in the open that Seth Rich was the wikileaks source, if that is indeed the case, which it certainly appears to be.
It does not matter whether Rich was the leaker or not. LIke Podesta pointed out. FOr us, the important thing is tying Podesta to the murder.