(1) First off, try doing
This will actually return you:
"display": "Visit Diagnoses: Presumed diagnosis, G0P0000, Primary",
If you add
&v=full to the response, it will be more verbose. Perhaps this will give you some of what you're looking for.
(2) If you're looking to add a REST resource that gives you the diagnoses for the patient, then the simplest way is to add a new Controller, that handles a request like "/emrapi/patientdiagnoses" that you annotate with @ResponseBody and you have it return a
List<Diagnosis>. (I'm not sure this will actually work, and you might have to simplify the Diagnosis object to something that can be automatically converted to JSON.