Hello Sam3,
A member of the organization can only delete the contacts they have added.
So, if you add two of your contacts and made them public, your teammates cannot delete them. They will, however, be able to see them and aee their details (like phone number and email address), if you have added these to the contact.
All contacts that you have inserted in the organization Contact Manager can be edited by you and you can make them private or public, change their details or delete them altogether.