I believe that 580715 Joyce was awarded the MM for POW activities in the London Gazette 14 Nov 1944 but that it was cancelled in the London Gazette 4 June 1946 where he was identified as 580715 Sergeant (now Flying Officer) Michael Joseph Joyce RAF. Wasnt he cousin of Lord Haw Haw and worked for the Germans.
Warrant Officer (580715) Michael Joseph JOYCE had been commissioned Pilot Officer (51894). 24 Feb 1943. I hadnt seen any ref to the Richard name