Personally I'd just find a new home for the mean RIR. My RIR's are my favorites and very sweet - but I hand raised them. Who knows what yours has been through or maybe she's just a grump girl.
I think you'll rest easier if you don't have to worry about her attacking your other girls and chicks.
I think you'll rest easier if you don't have to worry about her attacking your other girls and chicks.