Your course creator is a course creator in a category. When they go to that category -for example from the /course/index,php page - do they then see an option to create a course? I tested with a course creator in a category role and they could do this from the course/index.php page.
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Create courses
གྲོས་བསྟུན་འདི་བསྡམས་ཡོདཔ་ལས་ ལན་གསལ་བརྐྱབ་མི་ཚུགས་