What a relief! For tonight I would probably let her sleep with her chick friends, but make sure she isn’t sleeping on her back. It will take a little time for her to build up strength but as she perks up she will be more motivated to try standing on her own (with the brace on) before bed tonight you could do cup therapy for 10-20 mins. I love watching a tv show while holding a chick in a cup lol! Make sure the cup is narrow (think shot glass or small measuring cup) and put some paper towels in the bottom so she has traction. Then use your finger to help position her in standing position and you can assist her with your finger in the cup if she can’t stand on her own yet. You just don’t want her to get cold so don’t bring her out for too long.
Other than that, keep giving her sugar water/electrolytes and if possible, put it near her so she can start drinking and eating on her own. For food, more egg yolk, and you can mix it with some chick food (if the food isn’t ground up, put in a ziplock bag and use a cup or something heavy to smash up the crumbles so they are kind of dusty) and mix that in with a little yolk, or offer it plain, just in the dusty form and leave it near her.
You’re doing great! Keep it up!