Oh god i remember some years ago i had a row of 9 cages all holding single females , what a bloody nightmare , not one of them would live with another ferret, i had hells own game re homing them as single ferrets as at the time everyone wanted mixers to add to there supergroups of ferrets.
Personally i dont think its worth the stress trying if theres so much aggression , i would have 2 groups jule, ad another kit to the newbies group, i have never had one group here always had at least 2, which i have at the min 3 hobs & 1 jill kit & 1 single jill who is to long in the tooth to be