Has an AFL game ever ended 88-50?
Exactly once. On May 9, 2015, Sydney beat Melbourne 88-50, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 88-50 in league history.
That makes 88-50 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 89-50 has happened 5 times and 88-51 has happened 3 times.