Where does it say that the DNC admitted it? No nothing was proven in Court as the Judge dismissed the case.The lawsuit was rejected because they admitted it court they rigged it.
The whole point was that small donors put together a class action lawsuit to get their money back on the premise the DNC lied about the fair and open primary. The only way to stop that was to admit in open court that the Democratic party is a private organization not subject to any election rules. That they can at any time change the rules, drop a candidate later, whatever they want to do. That the primary system actually doesn't matter. And the votes don't matter either.
The judge accepted this. But in order to do so they DNC had to admit they rigged it. That is how they stopped having to pay back donations.
So yes it was proven in court.
You just make things up as you go along!!