Thank you; I read your initial response as sarcastic; my mistake. Optometrists are university-trained allied health practitioners. They provide eye health checks, currently one check in two years is claimable, and if disease is detected refer the patient to a medical specialist. In addition they check vision and sell spectacles etc. Vision checks can be claimed more frequently than eye health checks. Optometrists would not normally have access to a patient's general medical records, or optometry records with a different optometrist unless the patient brought them in, but they could check with Medicare as to when the patient last had a type of optometry service, because it might have been by a different optometrist and if too recent would affect claiming.
If Medicare records could be obtained that far back, it would be worth checking whether Marion had ever visited that optometrist before. An optometrist would recognize a regular patient, but likely not one returning for only the second or third visit after a number of years. (However you make a fair point that a return patient would be cross-checked against previous clinical notes and it's reasonable to think that in that case an impersonation would be detected.)
