They might fight when in with the hens, they might not. But I can practically guarantee that two roosters of decent size together will overbreed five hens. And he'd be lonely on his own.
So yeah, if you're determined to keep him, I'd probably separate the two roosters together, at least for the first year. After that (the initial surge of hormones), I might look into giving him a hen or pair of hens of his own. Pairs and trios often work out very well.
Or you could try giving him a run beside or inside your existing run so that he can interact with the others, but not go after the hens. And not be beaten up by Dad for the same.
So yeah, if you're determined to keep him, I'd probably separate the two roosters together, at least for the first year. After that (the initial surge of hormones), I might look into giving him a hen or pair of hens of his own. Pairs and trios often work out very well.
Or you could try giving him a run beside or inside your existing run so that he can interact with the others, but not go after the hens. And not be beaten up by Dad for the same.