A way to find out who has access to my Calendar
 

Hello, I have had a request from my HR department to find out who has access
to a certain calendar. I need to find out this information without the user
knowing I am looking. Is there a way to see who has access to a users
calendar without logging in to the users account.
I found the PFDAVAdmin software but it only shows public folder information.
Is there a similar tool to this for user mailboxes?

I am unable to go to the user's desk to check from Outlook.

Thanks,

Matt