Has a FIBA World Cup game ever ended 91-70?
Exactly once. On August 30, 2010, Argentina beat Angola 91-70, and no FIBA World Cup game before or since has ended that way. When it happened it was a scorigami, the first 91-70 in league history.
That makes 91-70 the 240th most common final score out of 863 that have ever occurred in FIBA World Cup. One point away, 92-70 has happened never and 91-71 has happened 2 times.