I too cannot comment on Adelaide, I am sorry, I am in NSW.
I had to have a brain MRI during chemotherapy as I was getting savage headaches.
my Oncologist referred me to one scan place that he said would do it bulk billed, but he had to write on the referral that the reason was connected to the chemotherapy.
The breast MRI I had done was only done at one PRP location near me. I paid for it.
The other PRP that did do them, only did them for the high risk women under 40 with family history and they bulk billed them.
I found the whole MRI thing very confusing.
I would suggest ringing and asking lots of questions, then you will find out the whole story.