Readers Digest version .....
The first lead detective (Hans Rupp) zeroed in on a local washing machine repairman who was in the process of receiving parts to fix the FGM's washing machine. This person has since sued the State of NSW and won, with the State contesting the payout. Hans Rupp had cleared both of the families (he was the one who ordered the forensic investigations of the FP property).
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The second lead detective (Gary Jubelin) was investigating a neighbour. He was pulled off the case and resigned, after making 4 recordings on his phone of conversations with the POI outside the warrant dates. He also had cleared both of the families.
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The third lead detective dug up an entire area at a riding school (where FM turned her car around to go back when searching for William) and found nothing. Simultaneously bringing the FP before the secretive NSW Crime Commission to answer questions, and having bugged their home for at least 9/10 months.
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In between there have been numerous local sex offenders investigated. The area has an unusually high amount of sex offenders living in it - likely due to the proximity to a prison and parole requirements upon release.
As well, there has been a Coronial inquest happening - one which is about to resume if no charges in relation to William are laid.