It's not hard to get accepted as an international student to the Australian medical schools. If you're really worried, at least apply to schools that do not hold interviews as back up.
Resources are minimal at Griffith for any international students.
As little as 3-4 years ago, there was only ever 2-3 international students at Griffith and they weren't all Canadian. Maybe one was per year. the majority of Canadians attend UQ in Brisbane, like 80-90 every year the last..god knows when. 6-8 years. (Before that it was 30-40 a year). There's no "critical mass" at Griffith. Also, going to emphasize this - Griffith takes in internationals for funding purposes, but it is still very much an Australian school at the end of the day (not an international school or "Canadian off shore" school). Staff are Australian. Most will never have been to Canada, let alone have any connections or even know what board exams are or what the Canadian match is. There are no board exams that Australian students take. There is no equivalent to the match in Australia. they all have a guaranteed internship year instead (domestics that is, not internationals) and it is not merit based for them, it is by lotto.
If you're hellbent on advising, you can try asking UQ students or ask about attending UQ seminar/events that are dedicated to the American and Canadian cohorts there - these are generally put on by UQ students and alumni. But it will all be in Brisbane. Or join the UQ facebook group and look for events that come up. the class sizes are so large at UQ anyway, likely no one will notice if you attend one of their lecture hall sized events. The Canadians of that cohort generally don't care either. (Ochsner Americans generally don't like to share - no offence to Ochsner peeps reading this - so I wouldn't go to their things). Or alternatively, suggest taht Griffith offers resources - as UQ does. But it is the only Australian school I'm aware of that does this.
As for facebook groups.
They exist for all Griffith students, there never used to enough international students for their own dedicated facebook group. I'm not going to post what it is on the world wide web. But google GUMSS That is their medical society and get in touch with their student reps and ask about facebook groups or international student representation from there.
It's been discussed in other threads more or less. But if your'e trying to match back, key things to look for is whether the offshore school you're attending has partnerships directly with other medical schools in whichever country it is you're trying to go back to. And critical mass. Alumni and upper year students able to help lower years. Considering how tiny Griffith's international cohort is, I very much doubt it will have this. It's not a requisite, but it makes your life much easier come 2nd, 3rd and 4th year.
Anyways, you guys have chosen Griffith - it's a good Australian school. But you will be on your own much of the time with regards to figuring out to match back to whatever it is your home country is.
Addit: Griffith domestic students will likely have already created 2018 facebook group for first years. Contact GUMSS.