Generally bobwhites are monogamous and mate for life with one bird. It is rare that one female will share her man with another female. Sometimes the male will except another female and sometimes not. Usually it is the females that attack the other females to keep her mate. You can try a trio, but I highly doubt it will work. I have NEVER had luck with this situation and I try all the time, mixing and matching birds in aviaries.
Now, if you offer them a LOT of space, you can sometimes keep a single female near a mated pair if the pair is docile enough.
Edit to add: During the first breeding season of young bob's, sometimes they ARE fairly docile and you can keep non paired birds together. However as these birds age, each year they become more and more aggressive.