have you tried putting them in the other 2's cage and not the dominant ones cage either that or swap them over put the 3 that get on in the cage you want them in then once the 3 are settled then put in the one causing trouble. I've also heard that masking their sents can help but thats only when putting a male you've used for mating back in with males he's been with before. I've never personally had females that have fort and come off bad i've only had 2 dominant males get together by accident and rip each other apart. Females tend to squabble but if left to it usally sort out the pack order.