Is my meeting on Listener accessible to everyone in the organisation?

When a meeting is brought to Listener only you and the meeting collaborators (if any) can access it. You will have to add the meeting to a project to make it accessible to people in the organisation. They will have view access unless you add them as collaborators.

Note: Only editors in your organisation on Listener can be collaborators. To share the meeting with 'viewer' members you will have to add it to a project, they are a part of.