Is there a way to find out if an Approving Manager opened/viewed an attachment prior to approving an

Hello -

We are on E-Business Suite 12.1.2.  Senior Management asked if we could run a report which would identify if the Approving Manager of an expense report actually opened and reviewed the attachments prior to approving the expense report?   If so, can we also get the lengh of time between the opening of the attachment and the approval?

We do not use any Auditing feature in E-business suite.  Is there an "event" which occurs when the manager views the expense report attachment which could somehow be used? 

Does anyone know if this can be done and if so, how?

Any guidance would be greatly appreciated.