I agree that space is critical for any flock of chickens whether all-girl or mixed sex, all the same age or mixed ages. As fast as young chicks like yours grow it is easy for them to outgrow their space. Each chicken has its own personality. Some are fairly calm and take close confinement well, others simply do not. Sometimes you can get one that is a natural bully.
I don't know for sure what is happening with yours but it sounds like they have outgrown their space. When you fix up their outside space make sure to give them plenty. If you go by the minimums you often see on here those generally work for mature chickens but chickens going through puberty often need more.
I raise cockerels with my flock every year and never know what I will see. I have adults with mine which has some effects, the way I read your post they are all the same age so I'll skip some scenarios.
If you have more than one male in your flock they will determine which is dominant. That may be a fight to the death, it may be a pretty peaceful event. Sometimes it is determined by brute force, sometimes it is more by intimidation. As they go through puberty this can change on a dime. I consider having a place you can immediately separate a cockerel to be a good thing.
What I typically see, if there is any violence, is that they fight for a bit and one decides it is better to run away than continue to fight. It is key that they have enough room to run away and get away. Otherwise the winner doesn't understand he won and continues to attack. That can lead to dead cockerels.
I'll explain my "if there is any violence" comment. I typically have 10 to 15 cockerels growing up with the flock until they reach butcher age, 16 to 23 weeks of age. A few will fight and determine which is boss. Most don't get involved, at least by the time I butcher them.
Sometimes the process of a cockerel becoming the flock master is really peaceful when all the others are female and the same age. Often it is not that peaceful. Typically a cockerel will want to mate with them and they are not willing. He is not trying to fertilize eggs, they aren't even laying, it is purely an act of dominance. Sometimes the girls (or some of them) are willing but often they are not. It is fairly rare with immature cockerels and immature pullets that the pullets fight back. It can happen if you have a pullet with a strong dominant personality (especially if the boy has a weak personality) but usually not.
What I typically see is that the girls either squat and submit or they run away. He may let them run away or he may chase them down and force them to mate. I've never had a pullet injured when they are forced but it can be violent, injury is possible. Sometimes the pullets hang with the cockerel and just handle the mating and running away. Sometimes the pullets avoid the cockerel. I have enough room they just stay far away outside, but people with limited space often see the pullets staying in the coop and often on the roost to avoid him.
Again, I have no idea what you will see. I encourage you to provide as much room as reasonable, I believe this gives you a better chance of having a success. While I always observe to try to avoid injury I mostly consider this as chickens being chickens and doing what comes naturally. Part of doing what comes naturally is having enough room so they can manage it.
Good luck!
