Has an AFL game ever ended 29-9?
Exactly once. On July 16, 1898, Geelong beat Sydney 29-9, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 29-9 in league history.
That makes 29-9 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 30-9 has happened never and 29-10 has happened 1 times.