Has a World Baseball Classic game ever ended 16-7?
Exactly once. On September 22, 2012, Canada beat Germany 16-7, and no World Baseball Classic game before or since has ended that way. When it happened it was a scorigami, the first 16-7 in league history.
That makes 16-7 the 62nd most common final score out of 87 that have ever occurred in World Baseball Classic. One point away, 17-7 has happened 2 times and 16-8 has happened never.