A judge rules in a case only when the judge is finder of fact, as in a bench, or non-jury, trial. In your case there will be no trial, bench or otherwise, so there will be no finding of guilt or non-guilt, by anyone. Once all the evidence is suppressed, it is up to the charging agency to decide how they want to proceed. Generally, if they have no evidence they "drop" the charges. Dismissal is a court action and again, the court cannot dismiss the charges unless the state persists and you challenge the charge's validity - the State will not generally put the court in that position but I suppose it is possible.
The DMV is a regulatory agency, an animal of the executive branch of government, not the judicial branch. Regulatory agencies have constitutional support by act of congress, but your constitutional protection lies in the due process clause. As DMV decisions are eventually reviewable by the circuit court (the judicial branch), there is provided due process. This arrangement actually gives the agencies a lot of power as due process of law challenges are usually neither cheap nor timely. But, so long as you have an article III appeal process, it is considered constitutional.
Take the DUI school, that is the DMV caveat for getting back your license in this circumstance. It might offend your sensibilities after being accused in a legally suspect way to begin with, but as a practical matter, it is the easiest, fastest, and cheapest way to get back on the road legally. Do feel free to complain to the legislature though.
The above is a general explanation offered for educational purposes only. I hope it answered your questions.
Technically, if the state seeks to proceed without evidence, the judge would likely grant a motion for a directed verdict. In order to get a 'not guilty' verdict, I as the lawyer would not ask for a directed verdict. I would wait until the Judge gives the case to the jury. That way the jury can find the defendant 'not guilty' and the dmv would remove a DUBAL suspension. Typically, though, the state doesn't proceed if the evidence is suppressed. If that happens, then DMV will not remove the DUBAL suspension. In either scenario, a REFUSAL suspension would not be removed from the driving record.