Information on MLS is not warranted in any way, that's their disclaimer. Agents are only humans, they make mistakes, saying that the pool equipment was new and not specifying it was just the pool pump its not the greatest deal in the world. About having a "case for court"....you are admitting to knowing about the issue one month before closing yet, you moved forward with the closing, why did you? If you wanted the items fixed they should have been fixed before you closed.
Ultimately you need to ask the question to a legal counsel.