They require a Cert IV in T&A no matter what your qualifications are. It is just because you teach in a vocational educational institution or teach in an area related to workplace training. The lady was turned down not because of her Masters, but because she did not have the Certificate, which costs 1500 by the way. I agree that it is just silly to ask people to have a certificate on top of a Masters degree.
Yeah, secondary school teaching might be a better option, especially if you want to go to a remote rural area. It is quite difficult to find a permanent job in metropolitan areas, though Western Sydney, for instance, might be an option, too, for the brave. Still, sponsorship seems to be a dream more than reality.