Abaixo da consulta MySQL listará todos os seus cupons associados ao pedido.
SELECT pc.post_title AS coupon_name,
pc.post_excerpt AS coupon_description,
Max(CASE WHEN pmc.meta_key = 'discount_type' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS discount_type,
Max(CASE WHEN pmc.meta_key = 'coupon_amount' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS coupon_amount,
Max(CASE WHEN pmc.meta_key = 'product_ids' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS product_ids,
Max(CASE WHEN pmc.meta_key = 'product_categories' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS product_categories,
Max(CASE WHEN pmc.meta_key = 'customer_email' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS customer_email,
Max(CASE WHEN pmc.meta_key = 'usage_limit' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS usage_limit,
Max(CASE WHEN pmc.meta_key = 'usage_count' AND pc.`ID` = pmc.`post_id` THEN pmc.`meta_value` END) AS total_usaged,
po.ID AS order_id,
MAX(CASE WHEN pmo.meta_key = '_billing_email' AND po.ID = pmo.post_id THEN pmo.meta_value END) AS billing_email,
MAX(CASE WHEN pmo.meta_key = '_billing_first_name' AND po.ID = pmo.post_id THEN pmo.meta_value END) AS billing_first_name,
MAX(CASE WHEN pmo.meta_key = '_billing_last_name' AND po.ID = pmo.post_id THEN pmo.meta_value END) AS billing_last_name,
MAX(CASE WHEN pmo.meta_key = '_order_total' AND po.ID = pmo.post_id THEN pmo.meta_value END) AS order_total
FROM `wp_posts` AS pc
INNER JOIN `wp_postmeta` AS pmc ON pc.`ID` = pmc.`post_id`
INNER JOIN `wp_woocommerce_order_items` AS woi ON pc.post_title = woi.order_item_name
AND woi.order_item_type = 'coupon'
INNER JOIN `wp_posts` AS po ON woi.order_id = po.ID
AND po.post_type = 'shop_order'
AND po.post_status IN ('wc-completed', 'wc-processing', 'wc-refunded') -- Added needed order status over here.
INNER JOIN `wp_postmeta` AS pmo ON po.ID = pmo.post_id
WHERE pc.post_type = 'shop_coupon'
GROUP BY po.ID
ORDER BY pc.ID DESC,
po.ID DESC
LIMIT 0, 10 -- modify it accordingly.
Espero que isso ajude!