I was told at a recent birthday party by a person claiming to be a drinking partner of the detectives involved, so make of it what you want
His wife died in mysterious circumstances in an Arab country when he had an over seas posting, as females don't carry much weight over there, the death was never investigated, the police in Victoria were aware of this prior to the Wonagatta murders, via family members?. Evidently the accused was questioned 3 days after the disappearance was discovered, why don't know what alerted them, possibly video footage of him in the vicinity, credit card activity?
He purchased 10 (?) bags of lime and loaded it into a small trailer, when and where ?,evidently this again alerted police due to the quantity required to consume 2 bodies, possibly tracking his credit card?, detectives were unable to locate the trailer as it was sold on ebay
So the police had a possible suspect with in days of the disappearance and were tracking him, via mobile?
If true, amazing police work and you have to give them credit
Law abiding people don't realise the extent of camera coverage, ability to track mobile phone signals and a myriad of other data crumbs we leave behind as part of our daily lives because we have nothing to hide.
Those who think they are smarter than others and up to no good get caught by the same data crumbs we don't care about. If he did it, I hope he gets his fair whack and some.