I believe that Lt Cdr John Kerans, the Naval Attache who was sent to Amethyst to take command and fought her out of the river and back to the Fleet, never made Commander. Such is the gratitude of their Lordships!
John Kerans was promoted to Commander having received the DSO for his Amethyst exploits. There's a photograph of him somewhere with Richard Todd (the actor who portrayed him) wearing his scrambled egg cap.
He was rather too fond of the booze and paid the price, sadly. I liked him-- and thought him rather good company.
He died in 1985.