Custom post type not mailing

My regular posts show up in the digest email, my cpt does not. Any ideas? In my functions.php I have added the following:

function my_post_types($types) {
    $types[] = 'super_user_update';
    return $types;
}

add_filter('s2_post_types', 'my_post_types');

and my cpt

function register_cpt_super_user_update() {

    $labels = array(
        'name' => _x( 'Super User Updates', 'super_user_update' ),
        'singular_name' => _x( 'Super User Update', 'super_user_update' ),
        'add_new' => _x( 'Add New', 'super_user_update' ),
        'add_new_item' => _x( 'Add New Super User Update', 'super_user_update' ),
        'edit_item' => _x( 'Edit Super User Update', 'super_user_update' ),
        'new_item' => _x( 'New Super User Update', 'super_user_update' ),
        'view_item' => _x( 'View Super User Update', 'super_user_update' ),
        'search_items' => _x( 'Search Super User Updates', 'super_user_update' ),
        'not_found' => _x( 'No super user updates found', 'super_user_update' ),
        'not_found_in_trash' => _x( 'No super user updates found in Trash', 'super_user_update' ),
        'parent_item_colon' => _x( 'Parent Super User Update:', 'super_user_update' ),
        'menu_name' => _x( 'Super User Updates', 'super_user_update' ),
    );

    $args = array(
        'labels' => $labels,
        'hierarchical' => false,
        'supports' => array( 'title', 'editor', 'excerpt', 'author', 'thumbnail', 'trackbacks', 'custom-fields', 'comments', 'revisions', 'page-attributes' ),
        'taxonomies' => array( 'tminus', 'deployments', 'super_user_tags', 'category' ),
        'public' => true,
        'show_ui' => true,
        'show_in_menu' => true,
        'menu_position' => 5,
        'show_in_nav_menus' => false,
        'publicly_queryable' => true,
        'exclude_from_search' => false,
        'has_archive' => true,
        'query_var' => true,
        'can_export' => true,
        'rewrite' => true,
        'capability_type' => 'post'
    );
    register_post_type( 'super_user_update', $args );
}

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