At a guess and this is only a guess but I would suggest York House Cemetery may have been a local cemetery or one attached to the hospital he would have been taken to and later he was reburied in a Commonwealth military cemetery.
It is amazing what you can find online...
Death: Jul. 23, 1917
Inscription: Canadian Labour Corps
Burial: La Laiterie Military Cemetery
West Flanders (West-Vlaanderen), Belgium
Plot: X. A. 2.
Created by: International Wargraves ...
Record added: Nov 06, 2008
Find A Grave Memorial# 31191201 http://www.findagrave.com/cgi-bin/fg...&GRid=31191201