Where a plaintiff’s causation expert admitted to never considering several alternate causes of plaintiff’s injury, the U.S. District Court did not abuse discretion in finding the expert’s testimony unreliable and granting summary judgment to the employer.The 7th U.S. Circuit Court of Appeals affirmed a decision by U.S. District Judge Pamela Pepper, Eastern District of Wisconsin.Jeffery Kopplin worked for Wisconsin Central Railroad. In January 2014, Kopplin was operating a train at the Fond du Lac, Wis …