It definitely looks like that "smaller" buck has a 3rd antler growing out of the left side of his head. Good news is you can go after the big boy, and that 3rd antler should grow back next year. Scientists have successfully grafted antlers onto different parts of a deer's body (for what reason I do not know) and they continue to grow back year after year. It could be a tine from another buck that broke off in that deer's face during a fight, but there doesnt seem to be much inflamation around the wound, which makes me think it's an actual antler growing out of that deer's head. Great pictures!