Users Select inside custom metabox

I’m using human made’s custom meta boxes framework (https://github.com/humanmade/Custom-Meta-Boxes). I want to add a select drop down in my metabox wich is populated from the users with multiple roles on my WP site. Referencing this post : Get multiple roles with get_users

I came up with:

add_filter( 'cmb_meta_boxes', 'users_metabox' );

function eusers_metabox( array $meta_boxes ) {

    $prefix = 'user_';

    global $wpdb;
    $blog_id = get_current_blog_id();

    $user_query = new WP_User_Query( array(
        'meta_query' => array(
            'relation' => 'OR',
            array(
                'key' => $wpdb->get_blog_prefix( $blog_id ) . 'capabilities',
                'value' => 'Administrator',
                'compare' => 'like'
              ),
            array(
                'key' => $wpdb->get_blog_prefix( $blog_id ) . 'capabilities',
                'value' => 'Editor',
                'compare' => 'like'
              )
          )
      ) 
    );

    $fields = array(
    array( 
            'id'   => $prefix . 'user_sub', 
            'name' => 'Subscriber User', 
            'type'     => 'select',
            'use_ajax' => false,
            'options'  => $user_query,  // this is where you populate the select in metabox
        ),
    );

    $meta_boxes[] = array(
        'title' => 'Location Info',
        'pages' => 'em_users',
        'context'    => 'normal',
        'priority'   => 'high',
        'fields' => $fields
    );

    return $meta_boxes; 

}

Works somewhat, but seems to return just capital letters. Any ideas?

Need to output (UserID) as variable constant

Solutions Collecting From Web of "Users Select inside custom metabox"

I think the problem is you are passing the WP_User_Query object, not the results of the query. Try to change:

$fields = array(
array( 
        'id'   => $prefix . 'user_sub', 
        'name' => 'Subscriber User', 
        'type'     => 'select',
        'use_ajax' => false,
        'options'  => $user_query,  // this is where you populate the select in metabox
    ),
);

To:

$users_ids = array();
if ( !empty( $user_query->results )){
    foreach($user_query->results as $user){
        $users_ids[] = $user->ID;
    }
}

$fields = array(
array( 
        'id'   => $prefix . 'user_sub', 
        'name' => 'Subscriber User', 
        'type'     => 'select',
        'use_ajax' => false,
        'options'  => $users_ids,  // this is where you populate the select in metabox
    ),
);