I know regarding HIPAA, Aurora isn't supported but mySQL is. Maybe there's a reason why it's not HIPAA compliant that made it unusable for Netflix? And cost?
What aspects of HIPAA does Aurora cause problems for which wouldn't be a problem for other storage engines? The Aurora engine RDS product supports all of the normal MySQL access controls, SSL in transit and at-rest encryption for the data, snapshots and backups.
I don't believe it's a technical problem. It just hasn't completed the internal AWS process for HIPAA certification to be added to their BAA. Postgres is in the same boat.
Where is the intersection between HIPPA and a back-office customer billing system?