So I called UNSW Med, and they weren't able to help me with removing PMQ from my preferences as there was no one from the medial faculty there (they'll be available on the 6th of January - which isn't great as preferences close on the 5th). The person who answered said that I was free to email MESO but said it was unlikely for them to be able to change it, and basically said that I should have good luck and hope to not get PMQ.
I was also hoping to get some statistics of how many non-rural kids actually go to PMQ, but was unable to receive an answer on it. I think I'll have to do what
A1 suggested, although I'm sorta sceptical that they'll tell me what offers (if any) I have...
Thanks everyone for all the help!