Our PowerApp is model driven and so uses CDS as the data source. Our Flow is also configured with a Common Data Service (current environment) trigger - and so uses the same data source as the PowerApp.
To our understanding, the licensing for the Flow should be covered under the PowerApps license. However, a user who has just a PowerApps license is unable to 'Turn on' the Flow, or edit the Flow.
How can Flows whose licensing emanates from a PowerApps license be edited or activated by users with a PowerApps license?
When you say "However, a user who has just a PowerApps license is unable to 'Turn on' the Flow, or edit the Flow." this seems to suggest that you want those users not only to "use" the flow but have "ownership" or "admin rights" over that flow.
The power apps license gives allows users to trigger and interact with flows created by other after they have created the connection when they launch the app. This happens without additional intervention. They can also create new flows in this environment using premium connectors, assuming they have the "environment maker" security role.
However, the "turn on" and "modify" features are only available to the flow "owner" or to a user with "environment admin role" through the solution.