Hi Florian,
We are limited in the amount of support we can provide for customizations, but I will try to help get you pointed in the right direction.
Please see our Themer’s Guide for an overview of how to customize particular Events Calendar views.
To customize the events that show in list view, you can copy and modify the-events-calendar/src/views/list/single-event.php into [your-theme]/tribe-events/list/single-event.php. You can use the function tribe_get_organizer_details() to output the organizer info within the template.
Thanks, and let me know if you have any other questions.
Sky