Well the only reason why I am not sure is cause I have one Roo that you can see in the third pic down...he is on the right....His comb and wattles are so much redder and larger then the others and his tail feathers are so much diffferent then these two. He is also much larger in size, his legs and stance are that of a roo where as the other two act skiddish and have straight tail feathers. I dont know I guess time will tell.
They may not look just like him, but if you look at the characteristics they have in common you can see that these are also cockerels (btw, how old is the third bird - if he is older the differences are likely attributable to that). These birds show male saddle feathering and dark, glossy, patchy patterning on the body - another male characteristic.