Okay so first off. Ask them to do a card search for the specific cards being charged. Ask them to find every account that has that card and cancel the subs/create refunds.

Ask to speak to a senior advisor. you can mention the card might be compromised and the card will be removed from apple moving forward. You will need a new payment method if you used that card.

Refund requests can be created by the advisor you speak with.

As for a coupon I'm not sure what that means. A payment method can only be added to an Apple ID physically as in someone has to add it on a device/pc with the exact card numbers so this isn't Apples fault you added cards to multiple apple id's and didn't remove them.