The panel to the left of your process canvas in Automator should have tabs for both Classic and Data Prep. Do you see that?
Data Prep tab is for anything built in DPS and should have a node for Workspace. Happy to setup a WebEx if this is translating to what you’re seeing.
I believe you can add workspaces into Automator. Sharing a link from the Help Guide here.: https://docs.datawatch.com/datawatchserver/monseradmin/desktop/adding_a_workspace.htm?rhsearch=workspaces&rhsyns=%20