Has an Olympic Baseball game ever ended 13-6?
Exactly once. On January 1, 1996, Japan beat Nicaragua 13-6, and no Olympic Baseball game before or since has ended that way. When it happened it was a scorigami, the first 13-6 in league history.
That makes 13-6 the 48th most common final score out of 87 that have ever occurred in Olympic Baseball. One point away, 14-6 has happened never and 13-7 has happened never.