I don't know, I don't think its probably a good idea to tell a 7 year old kid to hit an animal with a broom or spray it with a hose.
I understand that adults may do this to get a rooster in line but it could send a mixed message to a child and its still not a safe situation for her to be in.
I would not allow my children to hit an animal after the fact. If she had retaliated right after the attack that would be different, but to send her out there just to knock him around days later doesn't sit well with me.
If he flogged her bad enough where her face is scratched up, I would not trust him ever again around her and to send her out to a pen to hit him is more like antagonizing him.
It is actually quite reckless to put her in that position after what he already did to her.
If it were my child she would never be within a mile of that rooster.
Even if it appears to put him in his place, it may not really and the next time she heads out to the coop he could go after her, they do have amazing memories.
The poster of this thread already said that this rooster willl chase after their vehicle if this little girl is in it, he has it in for her and hitting him with a broom or spraying him with a hose is going to add fuel to the fire.
I understand some may not want to see this rooster end up in a pot, but there is the alternative of rehoming him, as long as whoever takes him understands why he is being gotten rid of.