I get the impression that the leaves are stalkless, but the photos are not good enough to tell. Flowers in lanceolata are 10 mm ore more, in xerophila much smaller. Can you comment on flower size? Both species are listed in the ACT Plant Census.
I've added another photo that may help with the leaf stalks - they're essentially sessile. Flower size, from recollection, was probably between 5 and 10 mm diameter. The leaves were generally about 4-6 cm long and about 10 mm wide from memory. The bush was about 1.3 m tall, beside the trail in forest, but not far from the saddle of Murrays Gap which opens out into boggy grassland.
Unfortunately all the measurements you gave could apply to either species. The petal number (2) suggests xerophila. Lanceolata usually has 4 petals, but sometimes 2. Being a male plant we cannot wait on the fruit to develop.