Has an Olympic Basketball (Men) game ever ended 99-78?
Exactly once. On July 31, 1992, Croatia beat Germany 99-78, and no Olympic Basketball (Men) game before or since has ended that way. When it happened it was a scorigami, the first 99-78 in league history.
That makes 99-78 the 126th most common final score out of 698 that have ever occurred in Olympic Basketball (Men). One point away, 100-78 has happened never and 99-79 has happened never.