When you mail something to the court, the clerk can only process it. If you contest the ticket you have to appear unless you do a trial by declaration. Apparently you didn't do that. The DMV cannot decide anything only the court can do it. You have to have the court modify the fine or else pay it.
This is also not a business question but a traffic one.
This is just my opinion and not a comprehensive answer. You assume the risk because this answer may not apply to your situation depending on the facts.