The Mossie 21-kill achievement doesn't have a photo attached to it. It should be one of these:
Branse Burbridge, seen in the last pic with his radar operator Bill Skelton. Burbridge began the war as a conscientious objector, Skelton later took up a role with the Church of England. In recent years, Burbridge has suffered from dementia, his family had to auction his medals to help pay for his care.
Edit - FWIW, Burbridge & Skelton flew radar-equipped night fighters. So far as I can tell, the top scorer on the FB.VI was (cough) Charlie Scherf, with 13.5 air-to-air, including five in one sortie, also a record for the Mosquito.
