The VA Health API that Apple is consuming for its Health app integration adheres to a standard (Fast Healthcare Interoperability Resources [FHIR]) and will be available for a multitude of approved, third-party developers to utilize.
We provide all of the data that can reasonably be mapped to the FHIR standard and it’s up to developers (and their apps) to determine what/how to expose the data. In the case of the panels, Apple is choosing not to render the data.
“Unreadable Data” in the Health app is not something that is unique to VA records. Other health record data integrations may appear this way as well.