oneworld - Circle Trip Explorer - routing and fares help please.

I would like to fly JNB-LHR-SIN(TRANSIT)-MEL-SYD-JNB.

I don't need to stop off in Asia, it is purely transit as I am unable to fly LHR-MEL hence I don't believe I should buy a 4 continent Circle Trip Explorer - or does that argument not work?

What are the prices for the Circle Trip Explorer tickets ex SA and also what are they priced ex Aus in J?

I am currently in Aus and may just depart from here.

B. Travel must be a Circle trip via the following routing:
A. AFRICA - SWP - ASIA - AFRICA vv
B. AFRICA - ASIA – EUROPE/MIDDLE EAST - AFRICA vv
C. AFRICA – EUROPE/MIDDLE EAST - ASIA - SWP - AFRICA vv
D. SWP - ASIA - AFRICA - SWP vv
E. SWP - AFRICA- EUROPE/MIDDLE EAST - ASIA - SWP vv
F. ASIA - SWP - AFRICA - ASIA vv
G. ASIA – EUROPE/MIDDLE EAST - AFRICA - ASIA vv
H. ASIA – EUROPE/ MIDDLE EAST - AFRICA - SWP - ASIA vv
I. EUROPE/ MIDDLE EAST - ASIA - AFRICA – EUROPE/ MIDDLE EAST vv
J. EUROPE/ MIDDLE EAST - AFRICA - SWP - ASIA - EUROPE/MIDDLE EAST vv
Note: For items (C), (E) and (J) on a direct single plane service or when transfer without stopover is
utilised between SWP-EUROPE this will be considered a 4 continent journey.
xONEWC3's are not possible when both SWP and Europe are included.
The only way an xONEWC3 is possible at all is using HKG-JNB.

ex-JNB (ZAR)
LONEWC4 21800
DONEWC4 48000
AONEWC4 72900

ex-SYD (AUD)
LONEWC4 3899
DONEWC4 11999
AONEWC4 17399