Restrict media access except for uploading featured image

Hi, i installed your plugin and it works flawless. I even created custom roles for other plugins ??
Now I want for one certain role fully restricted access to the media library. but still the ability to upload a featured image.
If I check ‘upload files’ and leave alle other media capabilities blank, users can upload, but also acces the media library. If I uncheck every media capability, users cannot acces the media library but also not upload a featured image.
I checked the concerning plugin (https://github.com/liedekef/events-made-easy) but there’s no custom access for uploading featured image.
Can you help?

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