WordPress: Get posts from multisite sites (not main site)

gistfile1.php

<?php

$sites = wp_get_sites();

foreach($sites as $site) :

    // Only subsites
    if (!is_main_site($site['blog_id'])) :

        // Connect to new multisite
        switch_to_blog($site['blog_id']);

        $case_args = array(
            'post_type'        => 'case',
            'posts_per_page'   => 3,
            'orderby'          => 'date',
            'order'            => 'DESC',
            );

        $latest_cases = new WP_Query($case_args);

        if ( $latest_cases->have_posts() ) : ?>

                <?php while ( $latest_cases->have_posts() ) : $latest_cases->the_post(); $count++;

                if ( has_post_thumbnail() ) :

                    $featured_image = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'large' );
                    $featured_image_url = $featured_image['0'];

                endif;

                ?>

            
                <a href="<?php the_permalink(); ?>">
                    <figure style="background-image: url('<?php echo $featured_image_url; ?>')"></figure>
                    <div class="case__slider__text">
                        <h3><?php the_title(); ?></h3>
                        <p><?php the_excerpt(); ?></p>
                    </div>
                </a>
                    
                <?php endwhile; ?>

        <?php endif; ?>
        <?php wp_reset_query();

        // Quit multisite connection
        restore_current_blog();

    endif;

endforeach; ?>