We have no access to your account or messages from eBay so cannot see these pictures, but can tell you do not relist that item or you will face serious selling restrictions.
Did the email tell you you can relist the item with different pictures? If not, then do not relist.
If you see others using those photos, it's because the site is vast, with over 7 billion listings on at any one time so not possible to check each and every one. When they are spotted and reported like yours was, and break a selling regulation, they too will be removed.
