Forum Discussion
Sharepoint List From Excel with bi-directional updating?
The two way sync between SharePoint and any generated lists was removed in SharePoint 2007, a very long time ago. Microsoft did come up with an Excel add-in for Excel 2007 & SharePoint 2007 that's still floating about that may be of some use for you. If I can find it, I'll edit the post with the link otherwise the solution was documented on Code Project https://www.codeproject.com/Articles/134054/Restoring-Two-Way-Synchronization-on-SharePoint-Li.
A better way may be to have the manager simply maintain the SharePoint list rather than a spreadsheet. Any spreadsheet generated from SharePoint does retain a data connection to the parent list. The refresh frequency can be configured in Excel to pull down any edits to the source list on a frequent basis.