Usually with Cortinarius archeri s.l. one can see evidence of remnants of the cortina on the stipe or perhaps at the edge of the cap, such evidence seems absent on the upturned specimen. Cap colour and texture can change depending of recent rain and as the fruitbody ages. Is there any chance these were growing on wood or buried wood?
Looks very similar to this sighting of yours; https://admin-canberra.naturemapr.org/Community/Sightings/Details/4259701. So, presumably another example of the species - but with the veil remnant having disappeared.