“The Russians did it” is a total red herring. It’s a media/DNC ruse to take the contents of the emails off the front pages. If Putin had the emails, he would work to get Hillary elected, and then use them to blackmail her.
You bring up the best point: if the Russians did it, the Russians would want control of how it was used. They wouldn’t just hand it over to Assange like a kid who found a wallet full of cash and is giving it to the teacher.
NBC joins the “change the subject” effort by the DNC.
No surprise here.