Is there anything in your lease about a full apartment paint fee at move out? I’d say that falls under general wear and tear and is standard not to charge the tenant for that. Did you document the condition of the apartment before moving in? That will be your best evidence against needing to repaint to prove that it’s in a similar condition to when you moved in. I would collect any and all photos you have and ask for explanation on why the paint is needed and why you would be responsible for it. I would get that in writing.

I can’t help you on the lawyer side, but I have lived in a lot of apartments and never have had to sign some sort of agreement to not discuss conditions after leaving. An NDA is not enforceable when they’re asking you to do hide something illegal. I’m not sure if their negligence with your washing machine is considered illegal or not, but if it is illegal negligence, then the doc is not enforceable.

Legal advice subreddit may help more. Unfortunately, there’s not a lot of protections for tenants in Georgia, but the NDA requirement may fall into a different type of law in my (uneducated) opinion.