Offers from UoN are made based on ATAR, interview and UCAT. Interview offers are made before ATARs are even released using your UCAT score and so long as you do well in the interview (idk how they structure their interviews though last I checked it was like an MMI and a skills assessment) and pass their ATAR benchmark (94.30 for general applicantsI believe) then it's possible you will be accepted so your ATAR above 94.30 doesn't matter. IE a person with a 99 ATAR but crap interview is less likely to get in compared to a 96 ATAR and a really great interview, so ATAR doesn't matter and is simply a hurdle.
Since you can't get in without an interview, I would say try and get as high a UCAT score as possible to increase your chances of getting an interview, 90th percentile may be not enough regardless of ATAR. Obviously though if you're rural the cut off for both ATAR and UCAT will be lower than general applicants.