The leaves of this plant seem to be too smooth around the edges for river lomatia, all the other sightings I have seen have a few bumps or serrations along the edges.
yeah the leaves of this species are usually toothed, its seems that is quite unusual but i dont think the flowers are those of a tasmania. see https://canberra.naturemapr.org/sightings/1974293 Lomatia myricoides (River Lomatia)