[Bill Walker]

I think you are referring to F/O Robert H. Laurence, DFC (note spelling of last name). He is mentioned several times in Hugh Halliday's book "Typhoon and Tempest, The Canadian Story" and appears to have been quite a character. He reports the combat in his own words on page 97, the two German aircraft spinning in from steep turns at low altitude, after Laurence attacked a German formation while returning from a train busting mission, to even up the numbers in a large scale engagement.

He finished his tour on January 14 1945, with 439 Squadron's highest air-to-air score at the time, 3 destroyed plus one probable. The total of 3 appears to include one on 1 January 1945, in RB233/F, and the two on 29 December. He earned a DFC for all this, and his considerable successes air to ground.