I just read somewhere that I can no longer find, that in California, at least if a judge rejects the negotiated sentence, the defendant may withdraw the guilty plea. Also just read that a judge may reject and agreement, but may not alter it. Here is a page that cites some cases, related to Plea Bargaining

I have been reading the documents filed by Polanski's attorneys linked above, and also court transcripts of his plea hearing.   It appears that the dismissal of the other charges was to be made at the time of sentencing, and that after Polanski made his plea, there was an adjournment, so that a psychiatric hearing could be begun. Apparently the trial never actually ended--so I am completely lost on what stands and what doesn't.