Got it.
Check your child theme functions.php file.

Line #174 will never work:

   if (!current_user_can('hetbakenbeheren' or 'jaarboekje' or 'kerkdienstplanning')) {

as such role this expression “‘hetbakenbeheren’ or ‘jaarboekje’ or ‘kerkdienstplanning'” is evaluated to a boolean result, but current_user_can() function wait that its argument will be a string with a role ID.
You have to use this code:

function show_full_list_of_attachments($show_all) {
   //if (!current_user_can('hetbakenbeheren' or 'jaarboekje' or 'kerkdienstplanning')) {
    $current_user = wp_get_current_user();
    if (!in_array('hetbakenbeheren', $current_user->roles) && !in_array('jaarboekje', $current_user->roles) && 
        !in_array('kerkdienstplanning', $current_user->roles)) {
     return $show_all;
   return true;

In order users with one of those 3 roles see full list of attachments, but any other restricted user will still see just his own attachments in the Media Library.