Food for thought
IMO Somebody who was "in the know" between after the raid and before the media announced it, was asked by MC to drive her to her hideaway. She would not have gone on public transport. AK's Audi nor her car would have been used. As we have found out recently that she went to the Mollymook area on school camps, it is very likely an isolated Airbnb was booked in a different name for 3 months in advance like this one at Bournda Beach.
Holiday Rentals, Homes, Experiences & Places - Airbnb
Also a rental car could have been hired during or after the raid. Food, shakes and other essentials taken so she did not have to shop, maybe if she went in a hurry, she simply wore the clothes she had on on the day of the raid - hence her ASICS were probably the only shoes she took - no Dior high heels needed. Keys are often just left in a secret place - so no need to meet the owner or real estate agent. Then this person/s went back to see her a few weeks before the shoe was found to ask her where all her money had gone, or angry with her that he/they would be implicated in her fraud, she then went into a narcissistic rage and violence occurred.
In this scenario, I am working on the theory that MC died about two weeks before the shoe was found as there were no barnacles on the shoe and decomposition was in process. This also suggests to me that the rest of her body could have been buried then. But the perpetrator decided that it would be a good idea to dislodge one of her feet from her decomposing body and plant it on this isolated beach. This could have been done to make it look as if the foot/shoe was washed into shore so police would assume she committed suicide.
Of course, there are three other possible scenarios:
1. Body was frozen in a very large freezer until the perpetrator decided to dump the body or had to be dismembered - hence the foot was cut off.
2. MC went swimming and drowned in large waves but how did the foot/shoe dislodge?
3. MC suicided by jumping off a cliff.
But, if she was suicidal, was MC able to get rid of the things she took with her before the owner or cleaner came to get the house ready for the next tenants? Otherwise, the perpetrator/s would have cleaned up afterwards and hidden the keys again perhaps leaving no trace - except for the cadaver dogs.
If I were the police I would be making enquiries in the Bournda Beach area.