FQDN value in strust for SAP Fiori working with Route 53

The customer wants to keep custom FQDN for DEV & QAS when lifting to AWS, and they need to create certs in strust for access via Fiori. In this case, do we put the custom FQDN or Route 53's FQDN when creating the cert in strust? I assume that it should just stay as is, because the connection to the DEV/QAS instances is resolved via private hosted zone of Route 53, where the custom FQDN is registered. Would you help confirm?