It's interesting that this stemmed from similar issues of an Amazon account using your details but with an email that doesn't match. There should be verification in place to enable you access to an account if you "no longer have access to your email account". This is often used as well in cases of domestic abuse. Of course, I'm not saying this is what happened to you but it's the same process to verify a person when they don't have access to a particular thing anymore :) So had they verified you are who you say you are then they should have allowed you to manage the refund of those items. Or at the very least arranged it for you.

What I'm curious about is the ordering of things and why someone would do it. I wonder if possibly to check the delivered status and therefore validity of the card and how much could be purchased at a given time so it could be used in other cases? I'd keep an eye on transactions on the card you use for Amazon just in case it triggers things elsewhere or elsewhere on Amazon.