I want all of the results to order by meta_value_num, but it's ordering by role first. How do I get them to ignore the role order? Here's my code:

$user_query = new WP_User_Query( array( 
    'meta_key' => 'Group',
    'meta_value' => $atts['bc'],
    'role__in'    => ['role1','role2','role3'],
    'orderby' => 'meta_value meta_value_num',
    'order' => 'ASC',
) );    
$users = $user_query->get_results();

I also tried array_merge but that didn't work either.