Not the best of photos to do an ID on but the leaf shape and opposite subsessile arrangement made me think of Opercularia, but only Opercularia diphylla, fits the characters and it is not known from our area
Interestingly we found it again recently in Tassie, also similar elevation. An expert with us, suggested it could be a strange rust-affected specimen of Gonocarpus tetragynus? Every specimen we found had small brown rusty 'glands' on the back of the leaf.
Yes, I agree re lack of leaf serrations, but Gonocarpus was also in the Tassie and Top Hut sites, though I cannot remember about the Mt Clear site. It could be something to still be puzzling over when the next session rolls around!!(The Tassie expert was Mark Wapstra.)