This commentator explains things pretty well: "The Mariinsky has cut the extraordinarily beautiful finale Balanchine incorporated around 1976 to the very moving music for death of Mélisande in Fauré's Pélleas et Melisande. It changes the "take-away" character of the piece from what is shown here as just another allegro finale, to one of rapt melancholy, as dancers, almost one-by-one take leave of the stage, finally leaving only three of the boys walking diagonally across the stage to the front, and finally coming to rest in a genuflection with an arm outstretched beseeching? in awe? the courtain slowly falling. Very apt conclusion, very moving if somewhat mysterious, somewhat analogous in feeling to the soloist carried aloft at the end of Serenade. To see this ending, arguably Balanchine's final thought on Emeralds ("arguably" because Balanchine was a known tinkerer with his pieces,.e.g. Apollo) you need to see the Paris Opera Ballet performance."
Since the commentator mentions Balanchine tinkering on Apollo, I figure that puts us back on topic. ;)
Thanks for all the information about Balanchine stagers, Helene.