There are several ways to see the request and approval history for any book in your account.
From the book's Title Details page:
Click Manage Titles and select or search for the book. Click on the book to view the Title Details page, and scroll down to the Requests section on the left-hand side. Choose Approval History.
From this page you can view the complete request history for this book, showing all members who have access to the book, via widget invite, request approval, auto-approval, wishes granted, or Read Now access. You can also access your Detailed Activity report, which will provide you with an Excel-based report of all activity for this title.
From the Manage Requests page:
If the book currently has Pending Requests, you can also click on the Requests tab, then on the Pending Requests button for the book.
From here, click "View History" to view the complete request history for this book. You can also download the Excel-based Detailed Activity report from this page.