Hi, I also hope that the Mizzou ladies here on GC can answer your questions. You might want to double-check the Mizzoou Panhellenic web site at
http://www.missouri.edu/~stulife/greeklife/phc.htm
And also take a look at the booklet that you received after they got your registration. On the web site this is what they say about clothes for the 9-party day (skits and some house tours):
"Dress for the day is slightly dressier than shorts -- a sundress, skirt or capri outfit is perfect, and . . . wear comfortable shoes." So
IF what you're thinking of seems to fit with that general description, it should be all right. IF you decide to go with a sundress or skirt outfit, you may want to keep in mind that you'll probably be sitting during part of the parties, so the dress or skirt ought to allow for comfortable sitting and getting up (not too short, in other words).
Women currently in college or recent alums will be better than I am at advising whether what you described is along the lines of what the Mizzou Panhellenic web site recommends.
Best wishes.