The author of that damning email uses the collective 'we', so presumably more than one person is prepared to back up the allegations. They should go to the Australian Government whistleblower site where they can remain anonymous. Piss, or get off the pot.
Writing direct to CASA and circulating to the likes of me is unlikely to get a result, because frankly my dear, I don't give a damn what some cowboy training mob out in the desert does. I suspect CASA takes a similar position when it comes to training of foreign students. I won't be flying on any airline that employs these graduates, and CASA takes little interest in foreign carrier standards.