To my current and limited knowledge, the only explorers with cobalt-specific sulphide mineralization on the Australian mainland are CZN and CCZ (cobaltite with chalcopyrite, neighbours in Queensland). AML has chalcopyrite and sphalerite with some cobalt enrichment/replacement, COB has pyrite with cobalt, N27 has some siegenite (but is mostly weathered oxides). Whatever AML has, TKM (neighbour along the Fish River fault) probably also has to some degree. There's also PAN with chalcopyrite and pentlandite and some cobalt enrichment.
Incidentally, the cobalt mineralization in the DRC is actually a weathered oxide of a supergene linnaeite deposit, producing the thrice-concentrated mineral heterogenite (90% Co2O3, or 64% Co metal). It thus occurs within the regolith which makes artisanal mining possible. The second most important primary cobalt mineral is the hydrothermal erythrite (erythros = red, "cobalt bloom") from Bou Azzer, Morocco, which is an arsenide, like cobaltite.
mindat.org has more instances of cobaltite in Australia in historical mines etc. Glencore's Mt Isa was a big one. Nearby Mt Cobalt reportedly produced famous erythrite specimens, but exploration today is asbolite oxide focused (ANW).
