Ann: Strategic Investment from Sichuan Hebang Biotechnology, page-28

MINING OR PRODUCTION TENEMENTSAcquisitions of interests in a mining or production tenement by foreign persons are notifiable and significant actions (regardless of the value — that is, a $0 threshold applies), except if acquired directly from an Australian government.https://foreigninvestment.gov.auPDFFIRB Treasury guidance note 24: Foreign investment in mining

IMO, almost zero chance of Aust govt allowing dull takeover. Also, most simple thing for govt to do now is add phosphate to critical minerals list and that will guarantee it.