Seems like the family may have done a one-to-one comparison against the 1979 Mundaring remains.was this the reason for a DNA profile to be looked into, so it could be compared to relatives of the missing man?
However with the current AFP program involving @othram this case should eventually work it's way through and the remains finally be identified.

National DNA Program partners with Othram to use forensic genetic genealogy for unsolved Australian cases | Australian Federal Police
26 October 2022 The AFP will have access to specialised forensic DNA testing, not currently available in Australia, to identify human remains and develop new leads for unsolved crimes, by partnering with a world-leading forensic genomics laboratory.