One obvious fault with him being a Old English, he has yellow legs. He would be an American game, and yes the cocks won't get along if they're true games even if raised together. Looks like a fine looking bird; but telling his individual line is difficult and not real important. I say he looks similar to a Kelso, but then some Clarets, Democrats, Radio, Yellow Legged Hatch, Butcher, etc. Look very similar as well.
I didn't even look at his leg color. Although, if he's hatchery, who knows what color legs he may have? And, i didn't mean OEG bantam, I meant large fowl Old English. He's far too large to be an OEGB. I have the OEGBs and have had them for about 10 years.
Anyway, he looks like some sort of game. Definitely not a modern game, too short of legs for that.