Has an Olympic Soccer (Men) game ever ended 11-3?
Exactly once. On June 9, 1928, Italy beat Egypt 11-3, and no Olympic Soccer (Men) game before or since has ended that way. When it happened it was a scorigami, the first 11-3 in league history.
That makes 11-3 the 17th most common final score out of 27 that have ever occurred in Olympic Soccer (Men). One point away, 12-3 has happened never and 11-4 has happened never.