Hi VHMJG
I am sure there are positives and negatives to doing the Certificate II course with Aviation Australia, however will it do anything for you to get a job with the airlines, no.
If you attend a recruitment day with
VB or QF you will go through exactly the same process that anyone who has not completed ths course will have to do, the only advantage maybe you may have had a chance to prepare and have your answers well rehersed however remember these recruiters interview 100's of people and they know awell rehersed answer when they hear it.
Also yes airlines will train you to their expectations and standards, so you won't avoid the ground school or an assessment centre recruitment day
If you want practice with preparing for interviews out there plenty of companies that do this for much less than $5,000
I know 2 people who did this course in anticipation of getting work they are still hopefuls 12 months after completing the course.
I am not knocking the course I am sure there are benefits to it, and there are airlines like strategic that will take people who have completed the course, as they want to save costs on training, but from what i have heard about this they still have to do ground schools.
Ultimately look at your work history customer service and hospitality, and your own abilities is what will see you achieve your dream not this course. Of course it's up to you
Best of luck, but really the course won't guarantee you this job