I asked the age as you had said "older hens" - understand now about how you came to have them.
Crowing hens are not nearly as common as some believe - yes, it does happen, but it is more of an exception than a rule. Can you get closer shots of the cochin's hackle and saddle areas - it may...
What is it that now has you questioning their gender? Both look to be female to me - though the brahma looks younger/less mature than the cochin. How old were you told each bird was? How long have you had them?
and