Can’t assign custom role to post as author

I cannot seem to show a specific role in the dropdown. I have tried assigning the custom role level_0, level_1, and level_2 depreciated permissions and that didn’t work. I then tried some of the code here:

function wpdocs_add_subscribers_to_dropdown( $query_args, $r ) {
  
    $query_args['role'] = array('yith_vendor');
 
    // Unset the 'who' as this defaults to the 'author' role
    unset( $query_args['who'] );
 
    return $query_args;
}
add_filter( 'wp_dropdown_users_args', 'wpdocs_add_subscribers_to_dropdown', 10, 2 );

It still won’t show. The name of the role is yith_vendor which came with the multi vendor plugin by yith. I have a custom post type made with JetEngine called “Artist” and trying to assign artists to users and it’s failing because yith_vendors don’t show as selectable as authors.

Here are the settings I have: https://i.ibb.co/ZmwvgN2/Screen-Shot-2021-07-05-at-5-03-08-AM.png