paul1980; You mentioned the existence of a psych profile for the perpetrator. Surely current advancements with D.N.A. profiling (which Police have) can offer information as to nationality (e.g. white Caucasian), blood groups, age approx. and family names. At the very least it could help via elimination. Though D.N.A. testing on bone and teeth may be better at pinpointing a person origins , surely Police have enough D.N.A. evidence to further refine their search, rather than wait for a match, much like waiting for 'death bed confessions' that never eventuate. The local University might help Police, as a worthy project.
While the perpetrator may have moved since, electricity account records will trace their whereabouts wherever they go if they're still on the grid (including any local short term renters).
It may seem an unconventional approach, but if Police had access to unrestricted funds, a request to other child sex abuse survivors, where the perpetrator was a family member... to place their D.N.A. on file, just to see what pops up in relation to other unsolved child, rape / murder crimes, would send a clear message to future offenders. While that could apply in a broad sense to 'anybody' unable to prosecute, name the family offender at the time (as a child), or where the perpetrator has since died, it could also be helpful to narrow down those living in the same area as Kylie back then. Police could simply target their request significant to Kylie, in this case other past child residents, the specific school area etc..
poor little angel