Has an AFL game ever ended 91-88?
It has. 91-88 has been a AFL final 3 times in 16,622 games. The first was Sydney beat Hawthorn on July 11, 1942; the latest was Geelong beat Richmond on April 27, 1996.
That makes 91-88 the 1534th most common final score out of 6,607 that have ever occurred in AFL. One point away, 92-88 has happened 8 times and 91-89 has happened 4 times. At one point the score disappeared for 40 years, between 1942 and 1982.