I have a similar situation...two mother hens (sat on each other's eggs)
chicks hatched and they both looked after them for a bit...then the "mean" mother hen started fending for herself, and being mean...so I separated her, and left the 4 chicks with the "nice" mother hen. The nice mother took in 2 bator chicks...then the "nice" mother after 4 days of letting these chicks under her wings started picking on them today (but not her two) Well I moved her as well...and the two baby chicks and the mother are losing their minds....but right now I want the 2 bator chicks to have some peace....I feel bad, but they are 8 weeks now...
not sure if its the right thing...just going with my gut