Custom SQL categories

Hi,

I use custom sql to find product category on my site based on sellerID :

$seller_id = (int) get_query_var('author');
$sql = "SELECT t.term_id,t.name, tt.parent FROM $wpdb->terms as t
                        LEFT JOIN $wpdb->term_taxonomy as tt on t.term_id = tt.term_id
                        LEFT JOIN $wpdb->term_relationships AS tr on tt.term_taxonomy_id = tr.term_taxonomy_id
                        LEFT JOIN $wpdb->posts AS p on tr.object_id = p.ID
                        WHERE tt.taxonomy = 'product_cat'
                        AND p.post_type = 'product'
                        AND p.post_status = 'publish'
                        AND p.post_author = $seller_id GROUP BY t.term_id";

            $categories = $wpdb->get_results( $sql );
$walker = new Dokan_Store_Category_Walker( $seller_id );

How can I include my result ($categories) in your plugin ?
Thanks