He wouldn’t have had a refund if he had downloaded the files.
It can happen if the customer changed his mind and didn’t download the item so in this case he could ask for a refund.
If I’m not wrong I think that you keep the same average rating on your profile.
If you don’t see your item anymore from the dashboard, then it means that it has been reviewed. Have you checked your spam folder ? You should have received an email.
Without asking permission you can’t.
It’s not allowed at all, even if you want to create a template and include a Codecanyon item, you’d need a permission from the author.