Has an AFL game ever ended 28-16?
Exactly once. On May 24, 1898, Essendon beat Carlton 28-16, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 28-16 in league history.
That makes 28-16 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 29-16 has happened never and 28-17 has happened never.