Our chickens made it very clear from the first time they saw the new chicks that they were out for blood, so we had to separate them. I don't think it helped that the mama was at the bottom of the pecking order!
We were able to have our guineas and chickens happily coexist. Even during breeding season, we never had a problem with the guineas. In fact, your chickens (hens) were definitely top of the pecking order.
We raised all of them on regular chick starter and later layer rations, but since they...
We had a free-ranged flock of guineas, which turned into a problem (LONG) story, so we keep our chickens in moveable tractors. Sure, it's some work to move each tractor once a day, but if they free-ranged, we'd have to stay outside all day to watch predators. We have a little of everything in...