Didn't meet Wallis but in about 1965, we did a school visit to Brooklands and were ushered into the great man's office in the old race control tower where we were told he still came in to work a few days per week; his Swallow VG models (used in the early experiments at Predannack(?) were there.
Years later in 1973 when I was training at Northern Radar, RAF Lindholme, the RAF bombing school had a Tallboy outside along with a Blue Steel.
More years later at Farnborough, I had the privilege of 'controlling' the Vulcan which did a flypast salute at his home in Surrey after he died.