hop flowers are allowed into australia provided you have a valid import permit.
after the customs declaration is lodged you need to submit all your paperwork to AQIS (customs declarations, bills of lading, commercial invoices, packing lists, packing declarations, manufacturers declarations, phytosanitary certificate with botanical names) for assessing. the consignment then needs to be inspected by an AQIS officer to ensure that it is free from any risk material and other horrible shit and then depending on which ICON case the hops fall under can be released (hops from NZ end use: processing) or be directed for mandatory treatment via heat treatment, ethylene oxide fumigation (allowed as an AQIS treatment but not allowed for use in food products by Food Standards Australia) or gamma irradiation (hops from all countries end use:All uses other than as animal foods, fertilisers or for growing purposes)
all of this costs $$$ so would only be worth it if you were a commercial importer of hop flowers.
pellets can come in without a permit because AQIS have deemed them to be so highly processed that there is no quarantine risk associated with them