According to the official SAS Viya 3.5 documentation, the deploy-casworker yml playbook should be used to add a CAS worker to an MPP environment and apply the latest hotfixes at the same time. You can find this information in the SAS Viya 3.5 Administering Guide page 38.

SAS Studio Enterprise is not a microservice, it's a web-based application that provides a programming interface, data visualization and an environment for managing analytics workflows, it's part of the SAS Viya suite of products.

SAS Studio Enterprise uses the workspace server, launcher server and the compute server, these servers are the core of the SAS Studio Enterprise's functionality, and they are responsible for performing various tasks related to data access, computation, and execution of SAS programs. The workspace server provides a web-based interface for working with data and SAS programs, while the launcher server manages the execution of SAS programs, and the compute server provides the computational resources for running SAS programs.