Change organizer logo size

To change organizer logo you need to pass extra argument in your default template function.
First override the template file content-single-event_listing-organizer.php.
Please check this doc for template override https://www.wp-eventmanager.com/template-files-override/
Copy the content-single-event_listing-organizer.php file to you theme side and then add extra parameter in display_organizer_logo('full') function.
Here you can add custom size too.