I'm not familiar with that feed. The analysis looks great, that's the percent of nutrients provided. The name says it is a mash which means it is ground into a powder but the photo shows it not ground. They tell you to provide grit which implies it needs to be ground up in their gizzard. They need grit for that so I'd make sure they are getting some grit.
Nine chicks one month old have a lot of room in a 42 square feet brooder. That is a huge amount of room. Overcrowding is not your problem. I've kept a lot more chicks in a smaller brooder until they were 5 weeks old without your problems.
What are your coldest temperatures. I don't know if that 60 degrees Fahrenheit is your high or low. Chicks a month old should be able to handle a low of 60 F.
It is not that they "should" be outside at a month old, but that they "can" as long as they can handle the temperatures. Broody hens often have their chicks out a day or two after they hatch. Some of us have the chicks out well before a month. We are all different with different conditions and set-ups, I try to not tell you what you should do but more of what you can do.
I don't know why that chick is pecking the others. I once had a 2-week-old being raised by a broody hen in over 2000 square feet of space kill a sibling by pecking it on the head. Not crowded at all. Then it started pecking another sibling on the head. That's when I noticed what was going on. I isolated that chick (2 weeks old but the weather was warm) for the rest of the day, probably 10 hours. I let it out to spend the night with the broody and its siblings. It stopped trying to kill its siblings.
Isolating them does not always work. You can try that if you wish but I think the vet is a viable option, especially if isolation does not work. I think this falls under the category of "solve for the peace of the flock". At the end of the day you and your flock will be happier without that chick if that chick can't learn to quit that pecking.