I had a leak in the bottom guest room of my newer home and it turned out to be condensation from the air conditioning duct above the ceiling.
As far a legal action, all you can do is hire a defect litigation attorney. They will get a third of any settlement that you receive and you will have to put up with the headache of dealing with people in and out of your house and the stress of waiting a long time. As far as disclosing the leaks, you will be better off repairing the leaks and you won’t have an issue with a home inspection. Also, your house is not under warranty for anything outside of structural damage which is hard to prove in court I would think.