Do you plan to register the car in the EU or have you already? Did you have to fill out any paperwork with the Swiss government or any EU country to bring the car in?
If the answers to the above are "no," it's possible you won't get anything.
The Swiss Authorities would have to contact the state where you car is registered to get information. While U.S, states share car registration information, I'm not sure how likely they would do that for a foreign country for something as minor as a traffic violation. Or how likely Switzerland would even bother.
But they might. Only time will tell. But I wouldn't lose sleep over this.