Get certified students with REST API

Hello,
We are trying to get all certified users in the course into our CRM system so that we can grant certificates to them automatically and list them in our CRM user cards.
With using the Rest API we are able to get the list of users who completed a course. But we couldn’t find the way to get only certified users.
How can we get the list of certifies users in a course with using Rest API?
Is there another way to get that information?