Publishing a Shared O365 Exchange MailBox Calendar to Sharepoint

Hi Everyone. Just getting started with Sharepoint under an Office 365 environment for a new client and have run into a problem. They have a pre-existing shared Mailbox "Events" which contains their events calendar. Being a shared exchange mailbox it does not have an Office 365 license assigned to it. The client would like to have this events calendar displayed on their new Sharepoint Team Site that I have completed, however adding the "Events" mailbox to the Calendar App does not display any content. Can anyone advise if it is possible to do this and if so how?