Hi,
I think that you must go to the user that you want to remove from RMCM in the CallManager user configuration and uncheck the 'ICD Ext' field.
When you do that the user will desapear from 'Resources' but the user continues available in the Historicals Reports. In this case you can not delete because they are statistics that the system stores and it would be no coherent to delete the statistics that could afect to the skills or CSQ performance.
Hope this helps,
Juan Luis
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