Hi @MCCLUSKEY, Daniel ,
As per my test Microsoft Graph bookingbusiness-publish, set the scheduling page of a business available to external customers, and it doesn't have the option to set this to Available to people in your organization.
As this is currently not supported by Microsoft Graph, request you to raise request from graph feedback portal and based on people requesting for similar feature and votes received will be reviewed by Microsoft Engineering team.
Hope this helps.
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