The Feres doctrine is misunderstood. The idea that soldiers and other beneficiaries don't have any recourse to remedy medical malpractice in the military system is a myth (perpetuated by the referenced article). Every hospital that I have worked at have a risk management department and a hospital attorney. These departments are constantly responding to inquiry requests (fishing expeditions) from civilian attorneys and also respond when a sentinel event occurs. The civilian attorneys understand that they cannot sue the military physicians for monetary damages, but they can and certainly do sue the federal government. When they sue the federal government, the suit lists all of the doctors who were even remotely related to the case. The only benefit that this provides to military physicians is that, unlike in the civilian world, the government will aggressively defend the case if it defendable.
When these events occur, or when they might occur, it is routine to have a medical case review board composed of peers (other physicians) who vote to determine if standard of care was met or not met. These boards are confidential, but the attorneys rely on them heavily. If it determined that the standard of care was not met, my guess is that the attorneys will settle with the plaintiff. Further, there are a myriad of remedies to be sought if standard of care was not met, or how egregious the offense was. They also rely on routine and frequent peer reviews, chart reviews, continuing education, etc. From my experience, Army medicine is hyper vigilant to ensure quality and safe care. Also, it has been my experience that is usually the civilian contractor doctors who are put into abeyance or have their privileges revoked.