Stewart's subsequent three week suspension - for which he was docked nine Dally M points - saw him finish the season on 18 points.
Had he not been suspended he would've finished equal with Marshall on 27 points, but with the added bonus of potentially polling votes in rounds 25 and 26.
Storm halfback Cronk can also count himself unlucky, having led Slater by one point before suffering an ankle injury that saw him miss rounds 24 and 25.
North Queensland skipper Johnathan Thurston lost his shot at becoming the first player to win three Dally M medals when he succumbed to a knee injury in State of Origin III.
Thurston, who led the voting on 24 points at that stage, did not poll another vote for the rest of the year.
Similarly, Cronulla's Paul Gallen faded as the season drew to a close and finished level with Thurston on 24 points.
But the night was clearly Slater's - or perhaps more accurately it was Melbourne's, with the club winning seven of the 20 awards on offer.
Skipper Cameron Smith added the hooker of the year, captain of the year and representative player of the year awards to his growing trophy cabinet, while Craig Bellamy was no surprise as coach of the year and Cronk stole the halfback of the year gong from Thurston.
Newcastle winger Akuila Uate, Manly centre Jamie Lyon, Gallen, Brisbane prop Sam Thaiday and Cowboys prop Matt Scott were all also named in the team of the year, while Nathan Hindmarsh again won the Provan-Summons fan-voted award.
Manly's Daly Cherry-Evans took home the rookie of the year, while Dragons youngster Jack de Belin was named the Toyota Cup player of the year.
-AAP