Health studies is a big field - thought about physio, occupational therapy, pathology, diversional therapy, optometry, dentistry, radiology/radiography, sports science, podiatry, etc? Not great wages but there's always nursing.
You said you might get about 70 UAI? That's the cut-off for CSU's Medical Science (available by distance too) which some people use as a stepping stone to postgrad Medicine (if you have the uni marks).
If you don't get into what you want, try getting in as an Associate Student... many (but not all) uni's allow you to enrol in a couple of subjects without being enrolled in the actual degree on a full fee basis (maybe paid for through FEE-HELP?). If you can show them that you are able to study at the uni level then that might get your foot in the door to get a Commonwealth supported (HECS place).
Some uni's also have Diploma of General Studies (with a lower entrance rank) which means you get a pretty piece of paper for doing 8 subjects (at 100, 200, and 300 level)... and if you do health related subjects you might get credit for what you really want to do plus the ability to get your foot in the door.
Enrol with Open Universities (no HSC needed) and get a degree from Monash, Swinburne, RMIT, UniSA, Macquarie etc. No health related degrees offered yet other than nursing, but having an Arts degree or a Business degree or even an IT one can help you to get into postgrad health studies. Actually read a few articles saying that there is going to be a big boom in Health Informatics (health/IT) in next five years, so maybe doing Information Systems would be handy. OUA do offer a postgrad Health Industry Management program.
There are health related courses at TAFE that you can do that may also open up doors for you.
What I am trying to say is move forward and sideways rather than taking a step back because you may waste a year for no benefit.