The Master Surname Index (not online) (mostly burials in Alberta cemeteries) of the Alberta Genealogical Society lists 7 Robert and 20 William McKenzie names;
Noyes Crossing is an old Post Office in the County of Lac Ste Anne. A bit more info as to year of birth and when they came to Canada would be helpful.
For further research please contact the AGS Research Services Committee of the Edmonton Branch,
http://www.compusmart.ab.ca/abgensocThe Edmonton Branch
http://agsedm.edmonton.ab.caPeter
for the AGS