Hello Kevin,
There's no option to exclude category through the report configuration page, so the solution can be to :
- Add all of your "report" products in a custom unpublished category and use it trough the "Category" option of your report configuration page
Or
- Set all of your "report" categories as children of a custom unpublished category which will be used through the "Category" option of your report configuration page, with the "Including sub categories" option enabled.
Kind regards,
Mohamed Thelji.