I wouldn't want to say yes that the mums would be okay, since in the ground they prefer full sun. OTOH, I can't really think of a reason that they wouldn't last through the fall days, better than when in the house! If you could find some short asters, I think they would do well for a few weeks; I have Purple Dome asters and think they are a bit more tolerant of partial shade. Otherwise, this is simply the season for saying goodbye to most of the flowers.

Too late to help you with this now but next year try some Bleeding Heart. They do well haning from pine trees in my back yard but be sure to keep them watered well.