I would appear that the Cessna 182 intended a landing at the oaks and had joined the down wind for runway 36. Why there were no comms from the 182 will probably never be known. Radio failure, wrong frequency, it may have given the pilots a false sense of security hearing nothing on the ctaf.
Not a fan of left and right circuits like we now have at cowra on 15-33 with all traffic to the west potentially going head to head. Traffic on a screen, could be a life saver or three.