wp query - WP Admin Dropdown List Filter for custom (ACF) field on custom post type(s)

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I have a custom post type called "resource" where files are uploaded by admins and made visible to selected subscribers. I'm using Advanced Custom Fields (ACF) to create a field called "visible_to", and this field allows the admin to indicate which subscribers get to see the post. The user name is displayed to admin and you can select 1 subscriber, many, or none for all subscribers to see the post. The selection gets stored as an array of user_id in wp_postmeta table.

In WP-Admin for the custom post type "resource", I'd like to use a similar dropdown list filter for admin to select the user name, click filter, and return a list of posts that are "visible_to" the selection or visible to all. So far I have successfully added a custom column, a dropdown list, and I have a query to return results. But I have 2 problems with my query.

Screenshot of the custom post type, dropdown list filter (All Visible To), and custom column (Visible To):

My code is based on the closest solution I could find here: Filter by custom field in custom post type on admin page

Problem: My problem revolves around my lack of understanding $query and parse_query filter. It is two-fold:

1. The $query in the code I'm using is pulling in the meta_value for "visible_to", which is an array of ID values. This is not user friendly. I want a list that shows the user name for each subscriber role, just like the first screenshot I posted above.

2. I've tried changing $query to return user_login from wp_users but I cannot join wp_users to wp_posts. Neither of my $query attempts have an effect on the results. All posts are returned, regardless of the list item selected.

Any help is much appreciated.

My code below.

    add_action('restrict_manage_posts', 'myehs_visible_to_dropdown');
    function myehs_visible_to_dropdown($post_type){
        
        global $wpdb;

    //Only add dropdown to the appropriate Custom Post Types
        if( $post_type !== 'resource' && $post_type !== 'manual' && $post_type !== 'news')
            return;

    //Grab data for the dropdown from the DB
            $query = $wpdb->prepare('
            SELECT DISTINCT pm.meta_value FROM %1$s pm
            LEFT JOIN %2$s p ON p.ID = pm.post_id
            WHERE pm.meta_key = "%3$s" 
            AND p.post_status = "%4$s" 
            AND p.post_type = "%5$s"
            ORDER BY "%3$s"',
            $wpdb->postmeta,
            $wpdb->posts,
            'visible_to', // Meta key
            'publish',         
            $post_type,
            'visible_to'
        );
        $results = $wpdb->get_col($query);

    //Ensure there are options to show
        if(empty($results))
            return;

    //Get selected option if there is one selected
    if (isset( $_GET['visible'] ) && $_GET['visible'] != '') {
        $selectedName = $_GET['visible'];
    } else {
        $selectedName = -1;
    }

    //Grab all of the options that should be shown
        $options[] = sprintf('<option value="-1">%1$s</option>', __('All Visible To'));
        foreach($results as $result) :
        if ($result == $selectedName) {
        $options[] = sprintf('<option value="%1$s" selected>%2$s</option>', esc_attr($result), $result);
            } else {
                $options[] = sprintf('<option value="%1$s">%2$s</option>', esc_attr($result), $result);
            }
        endforeach;

    //Output the dropdown menu
        echo '<select class="" id="visible" name="visible">';
        echo join("\n", $options);
        echo '</select>';

    }

    // Make selected dropdown return results
        add_filter( 'parse_query', 'myehs_filter_by_visible_to' );
        function  myehs_filter_by_visible_to($query) {
        global $pagenow;
        $current_page = isset( $_GET['post_type'] ) ? $_GET['post_type'] : '';
            // If we are in Admin and on the right post type and dropdown selection is made
            if ( is_admin() && 
                $pagenow == 'edit.php' && 
                $current_page == array('resource','manual','news')  && 
                isset( $_GET['visible'] ) && $_GET['visible'] !='' &&
                $query->is_main_query()) 
                // Return only posts where visible to matches the selection
                {
                    $query->query_vars['meta_key'] = 'visible_to'; 
                    $query->query_vars['meta_value'] = $_GET['visible'];
                    $query->query_vars['meta_compare'] = '=';
                }
        }

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