Mike, you have hit upon an interesting man (who some might term as a cad) with an interesting family. Public Family trees on Ancestry, Newspapers of the day and Dr Google provide a mass of information but do not fully answer your question.
Via Ancestry I can find him on a Remount Department Medal Roll showing he was issued with a QSA with the three clasps you mention. However, I can't find him on a QSA medal roll covering the date clasps or a KSA medal roll. What I can say is that if he did qualify for a KSA he did it by broken service in SA. The 31st March 1901 Census found him living at 26 First Avenue, Hove (as in Brighton), Sussex, England. Here is the relevant part of the the 1901 Census.
Mabel (nee Beddington later to become Mocatta) was his first wife, six year old Aubrey was to be killed in action in 1917 and I will let you count the servants.
The National Army Museum hold a telegram relating to him which might help answer your question - unfortunately it is not viewable on line.
Why a cad?
Like his eldest son, he served in the Great War first arriving at the Western Front in October 1914 and thus receiving all three campaign medals. He ended the war a Major and remarried. About the time his son was killed he had married a Molly Yearsley, ten years his junior.
This link tells all you need to know about Aubrey who had only returned to the trenches 48 hours before he was killed in action on 31 July 1917. He was first wounded in the Battle of Loos in September 1915, invalided home, complications meant he was not back to fighting fitness until July 1917.
www.jewsfww.uk/aubrey-john-simon-waley.php
His father (your man) died in 1945 in Kensington aged 74 - his death was announced in several papers but it appears to have been a very private funeral and no obituary, that I can find, subsequently appeared - which is a shame because it might have answered your question.
Regards, David.