Hey! Hope this reply isn't too late.
My understanding is that if you fulfil the maths prereq (either 25 raw in methods or successful completion of calc & prob online) and satisfy the other requirements, then yes you will be guaranteed a place.
I would suggest contacting Unimelb's FVAS just to be sure, though.
The graduate package will guarantee you a place as long as your WAM in year 1 and 2 is above 70. You must also enrol in the correct major and specialisation (animal heatlh and disease, specialising in veterinary bioscience), and fulfil any additional prereqs (eg. physics if you didn't do physics in VCE).
Let me know if you have any questions! I'm only in my first year of BSci/DVM but will try my best to answer
(ETA: forgot to mention that they recently changed the selection process to also include a situational judgement test for 2021 entry onwards.)