Yep. Merchan can declare a mistrial without prejudice due to the immunity ruling causing irreversible errors and kick it back to James if she wants to go full retard and go to trial again. If she does he will rule with the knowledge that the Supreme Court will immediately intervene because his court room will be a mini constitutional crisis.
Positives of that move is the dems gets to keep their "convicted by a jury of his peers got off on a technicality" talking point and no appeal to the Supremes. They also get to decide if they will go again in 4 years on the same charges when he gets out. Try to hang it like a sword for leverage.
All he has to do is probation and a small fine. That way he can avoid heat from Democrats who think he shouldn't get off the hook, and avoid heat from Republicans who think that putting him in prison or a stiff fine is politically motivated.
He actually can't do anything that doesn't give Trump access to appeals, though. If he tries to dismiss at this stage, sua sponte, it not only make him look like a political operator that disregarded all the previously raised legal issues (immunity, baseless charges notwithstanding, etc) but
also gives Trump more ammunition for his inevitable appeal. Remember, even Trump's indictment and arrest were legally improper and are still subject to being dismissed and expunged. If Merchan suddenly goes "lol the trial was faulty" then the next step is 'the indictment was faulty too'. Trying to split the baby and assign no jail time and a fine will only enrage the Democrats and also send the affair right to the appeal court.
The issue, the controversy, remains live and subject to appeal no matter what he will try to do. Merchan can't cleanly end this charade by trying to dismiss at this stage, it is legally impossible. There is no way to avoid a coming political and legal shitstorm, which goes to show how desperate and insane the Uniparty is to stop Orange Man.
Considering ti will go to appeals, that brings us to the shitshow that will be the appeal to the New York Court, which will be a brutal filing that is going to tear the trial judge apart for massive amounts of reversible error. (Not just on immunity, there are a lot of other issues but immunity is the biggest one since the SC made a ruling about it.) Its going to bring an incredible amount of scrutiny down on the judge, and put the appeals court in a real fix. None of their options are good.
1. They dismiss the case as being improperly brought due to immunity issues (or others), which is going to make them and Merchan look like fucking morons for not staying proceedings until the Supreme Court gave guidance or looking at the plain facts of the law. The Appeals Court even had the chance to intervene, and declined, so its egg on their face as well.
2. They send it back to be retried and in the course make the trial judge look like a total dipshit asshole
as well as themselves since they denied all interlocutory appeals. Trying to actually move this case forward under the Supreme Court's guidance would be practically impossible, but if they order it be done its going to be another shitshow that will generate tons of political capital....
for Trump.
3. Or they rubber stamp the entire affair and send to the Supreme Court, who will be extremely pissed off that they have to waste their time dealing with the bullshit caused by multiple lower judges ignoring the SC's opinion.