Modifying Author Link to add Author Meta in URL

I don’t know the context, but i got your use case working like this:

Add new permastruct and make sure to regenerate permalinks (Settings > Permalinks > Save)

/**
 * Add additional permalink
 *
 * @uses https://codex.wordpress.org/Plugin_API/Action_Reference/init
 */
function wpte_add_permastruct(){

    add_permastruct( '%author_trip_vendor%', 'operator/%author%', [
        'ep_mask' => EP_AUTHORS,
    ]);
}

add_action( 'init', 'wpte_add_permastruct' );

Added this to init action.

Next alter the WP Query on author query (is_author() === true condition)

/**
 * Change query when is_author() is true
 *
 * @uses https://codex.wordpress.org/Plugin_API/Action_Reference/pre_get_posts
 */
function wpse33150_alter_query($query) {

    // Do not apply if not $querying "author"
    if ( ! is_author() )
        return;

    // Set query for author meta
    $query->set( '_private_author_query', [
        [
            'key' => 'company_name',
            'value' => get_query_var('author_name'),
            'compare' => '=',
        ]
    ]);

    return $query;
}

add_action( 'pre_get_posts', 'wpse33150_alter_query' );

This is added to pre_gest_posts action

Now when you enter endpoint /operator/company-name the query will be altered to query by “company-name”.

Just for reference i’m also adding implementation of the author meta field.

/**
 * Add meta field company_name to user
 */
function wpse33150_user_profile_fields( $user ) { ?>
    <table class="form-table">
        <tr>
            <th>
                <label for="company_name"><?php _e('Company name'); ?></label>
            </th>
            <td>
                <input type="text" name="company_name" id="company_name" value="<?php echo esc_attr( get_the_author_meta( 'company_name', $user->ID ) ); ?>" class="regular-text" />
            </td>
        </tr>
    </table>
<?php }

add_action( 'show_user_profile', 'wpse33150_user_profile_fields' );
add_action( 'edit_user_profile', 'wpse33150_user_profile_fields' );

/**
 * Update meta field company_name to user on update
 */
function save_wpse33150_user_profile_fields( $user_id ) {
    if ( !current_user_can( 'edit_user', $user_id ) ) { 
        return false; 
    }

    update_user_meta( $user_id, 'company_name', $_POST['company_name'] );
}

add_action( 'personal_options_update', 'save_wpse33150_user_profile_fields' );
add_action( 'edit_user_profile_update', 'save_wpse33150_user_profile_fields' );