Great question, @EVant ! You can use client_credentials or account_credentials with the Server-to-server. See our Server-to-Server OAuth support documentation for a detailed description of the difference between account_credentials and client_credentials
Create a Server-to-Server OAuth app
https://marketplace.zoom.us/docs/guides/build/server-to-server-oauth-app/
The code snippet was actually provided via a successful Server-to-server Postman request.
Here is a screenshot of how the request was setup in Postman for context :


