The result wasn't what you're describing. The plaintiff was suing in federal court, with a constitutional cause of action. The defendants argued, and the court decided that the plaintiff has a medical malpractice cause of action in state court, which is appropriate for her to pursue (at least before a federal court will rule in her favor).
https://storage.courtlistener.com/recap/gov.uscourts.azd.985...
The result wasn't what you're describing. The plaintiff was suing in federal court, with a constitutional cause of action. The defendants argued, and the court decided that the plaintiff has a medical malpractice cause of action in state court, which is appropriate for her to pursue (at least before a federal court will rule in her favor).