Your routing is mel-nrt-sin-nrt-lhr-mct-lhr-hre-lhr-ord-lax-gru-nrt-hkg-akl-mel

Does this work? In two words "No, No"

First NO: You've violated the 2nd transit through Europe rule because one of the entries is not a "transfer without stopover between Ghana/Nigeria/Kenya/Uganda/Tanzania and another continent". Zimbabwe is not on the list. If you did it to say NBO or DAR then you'd be OK.

2nd NO: You are visiting Asia twice, but neither is "a transfer without stopover or on direct single plane service between the Southwest Pacific and Europe". Instead, you can either start by flying say MEL-LHR and leave all the Asian stopovers until the end of the journey, or have all your Asian stopovers at the start and then end the journey by flying from Sth Am back to SWP (e.g. SCL-AKL or EZE-SYD)