Just keep checking. Statute of limitations would be a defense in case it ever comes up again. You can't get a dismissal on a case the court doesn't know about.
I represent a girl on a DUI who bonded out and made her appearance before the clerk to enter her not guilty plea and get court dates. The clerk's office entered the NG plea but put the court dates in a different case. Her case is just sitting there in limbo, without court dates. MAYBE they'll find it someday, but if we raise the issue, they WILL find it and the government will do whatever it can to prosecute it.