I'm sorry, but those 2 pics don't show enough detail for me to make a call on either of them. I'm not seeing long, pointy feathers on the neck and just in front of the tail (clear signs of a roo in many breeds). I also can't see the comb of either bird, which is another place one looks for differences. It looks like one of your birds may have curvier feathers on the tail than the other, but depending on their breeding, that may or may not mean anything.