In regards to Marion noticing that Sally hadn't put the money into her account re the sale of the car, that's fairly good evidence that Marion did in fact return to Australia, is it not?
Not definitively. Marion probably didn't care about the money from the car. How much could it have been? 10k -20k? She wasn't strapped for cash. However someone else, like RB, who would have definitely known about all of Marions assets and loves money would more likely be annoyed the money hadn't been put in to the account he was trying to drain.