You don't seem to be understanding that age is the key here. Hens/female birds don't get red combs until they reach sexual maturity. That happens around 6ish months, give or take. Yes, mature hens have red combs and wattles. Sexually immature pullets do not. Yes, occasionally an older, dominant hen can crow, but it's way rarer than you'd think from trolling the interwebz. Any bird with a red comb or crowing under 4 months is a cockerel, plain and simple.
