Some of this is not quite what you are asking.
It would appear that Donald may be buried in SA with his daughter.

FORBES , Donald. 27 Jul 1925.
FORBES , Mary Margaret. Daughter of Donald and Rachel. 19 Feb 1982. Mother of Brian
Gnowangerup Cemetery
******************
birth
1891 492/344 FORBES Jessie Adelaide Kingsford Donald FORBES Rachel Wood Barossa
marriage
1921 288/523 MURRAY William Donovan FORBES Jessie Kingsford Adelaide Angaston
death
Saturday 15 January 1944 her death notice.

you might find someone else researching these families, which could lead to what you are actually after. cheers penne