A Cook County judge last week dismissed a counterclaim brought by a railroad claiming its employee should pay for property damage resulting from an incident that he alleges injured him.Circuit Judge John H. Ehrlich’s ruling last week touches on a debated question under the Federal Employers Liability Act — whether a defendant in a FELA case can file a counterclaim in the first place.Ehrlich’s 17-page ruling doesn’t definitively answer that question. But in dismissing Wisconsin Central Ltd.’s …