Kneeling? I don't know where people hear this stuff, probably in this forum. I'm having trouble envisioning how a cockerel could kneel, let alone that solving a problem.
I can't give you any guarantees of what will happen with living animals but many of us can tell you some of the things we've seen. Some typical happenings when you raise cockerels with the flock are that the rooster leaves the boys alone unless they start messing with his hens. Then he chases the boys away until they bother his hens again. Eventually some of the cockerels may mature to the point they challenge the rooster to become flock master. That can be a fight to the death or one runs away and the other is flock master. There can be repeat challenges from the loser or the winner may attack the loser every time they see them. It can be brutal. Or they can reach an accommodation where they work together to protect and fertilize the flock.
Sometimes no cockerel matures to the point they challenge the dominant rooster. They accept a subservient status. Often, if they have room, each rooster establishes a territory out of sight of the other and attracts whatever hens he can. They will know which one is dominant but I would not call that life miserable. Having a lot of room really helps your chances of being able to keep multiple roosters. If space is at all tight it often does not work out.
I firmly believe the fewer males you keep the better as long as you can meet your goals. But too many people successfully keep multiple roosters for it to always be horrible.