How could they really use the money anyways even if they transfer it to another account? I don't know how one could get away with it. Follow the money!
* Australia is part of the "West" here - ironic from a strictly geographic perspective
I am going off-topic here, because Australia is in question here, so perhaps replace my use of "US" with Australia and "American" with "Australian".
You can file an MLAT request
https://en.wikipedia.org/wiki/Mutual_legal_assistance_treaty
But it's a complex, time consuming process usually only done in cases of terrorism or espionage, not run of the mill fraud.
Pre self service on the internet call centers / mail in processors would have noticed if a large % of customers changed their payment details over a few days.