Typically regions differ in more than just frequency range, so that’s probably not a good idea, at least beyond initially showing that the hardware is not completely broken. Things like the number of channels, data rates, fallback receive windows, etc may be different - and also there may be unique regulatory requirements that the non-frequency settings from another region would violate.
You might check if the other LMiC repo I linked above may have more accurate region definitions.
Note that there exists both an AU915 and an AS923 you may need to figure out which is relevant, the LoRaWAN docs list both as potentially applicable to Australia.