You are welcome.
Also, I'm just going to warn you about making sure you quarantine new birds before introducing them to your flock.
I am telling you from personal experience, bio security is VERY important. You can possibly bring in a contagious/deadly disease with new birds and contaminate...
You should know for certain by 10-12 weeks that they are male or female. I am fairly sure that the darker two or your birds are females. I would go trade the cockeral in as soon as possible so they can all adjust to their new flock hierarchy. I wouldn't want to try introducing a new one to two...
The redish comb is not a 100% indicator at that age, as a late developing cockeral might have a tiny pale comb yet. Just pick one that has the smallest comb and thinnest legs. Leg thickness is usually a good indicator too, as males have thicker lags than females.