Urgent! Possible Mushy Chick disease, but no second brooder- Advice?

We have our fist batch of home hatched chicks, and one of them looks like it might have mushy chick disease- not much info of it online on how to care for the bird, accept stating that I should move it to a second clean brooder. We don’t have one? I can pick one up if need be but I want to get some advice first-

It might not be mushy chick disease but I think I see a little bit of a stump on its naval and there is a fluid sack on its butt near its leg.

Is there a risk of the bacteria being passed to the unlatched eggs? Do I need to move it to quarantine right now?

Most of the posts say that treatment isn’t helpful, but what can I do to best help the baby recover?

And lastly- is there a way to make a brooder from what I have already? Without needing to purchase a second one? Any help or advice is greatly appreciated

I didn’t include a photo because I don’t know what the rules on ‘medical injuries’ is and have been auto banned by a bot before for just saying the word injury- but tell me if you need one, I can try and comment with a photo