It took a while but I finally went through The Bourne in daylight yesterday, so stopped and took a look at Flight Lieutenant Waghorn's grave.
As was commented at the start of the thread, the graveyard is somewhat overgrown, however, given that according to the signs, the last burial was in 1967, this is not too surprising.
Flight Lieutenant Waghorn's grave is in good condition, albeit looking a bit empty without the eagle on the plinth and with a few weeds growing through the gravel. Some sympathetic tidying would help, but making it stand out from all the others may not be appreciated.
Unfortunately I was without camera and phone at the time, so no photos yet.
I found this on Youtube with some stills and film of the 1929 Race: