get_current_user_id()

Hi,

It is impossible, the class WP_User_Query does not accept the argument id and if you want to pass a function as a value of an argument, please use the code.

'query_args' => array(
    'role__in' => 'Administrator',
    'include' => get_current_user_id(),
),

And follow the documentation to know the list of accepted arguments.
https://developer.wordpress.org/reference/classes/wp_user_query/prepare_query/
https://docs.metabox.io/fields/user/#sample-code