Transfer Workspace Ownership (Manager Left Company)

My manager recently left the company and prior to her departure, she was supposed to transfer ownership of a few workspaces over to me. Unfortunately, this was forgotten about and she is still the Owner and I am the Admin. When I request ownership it says a notification will be sent to her to approve transferring the ownership to me but she has left the company already and her email is inactive. Any advice on what I can do in this situation? Note that I did try to work with IT to gain access to her email but apparently we can no longer do this.