Can we map multiple geo fencing locations to single staff?

Yes, you can select multiple locations for staff from the staff directory.
Web Dashboard -> Edit -> Access -> Select all the required locations available from the ‘Geofencing Locations’ dropdown.

Alternatively, If you are doing it from bulk then add all the locations separated by a comma can be added via bulk sheet.
Dashboard -> Staff Directory -> Bulk Upload -> Bulk Add/Edit (download sheet) -> Fill geofencing detials in detailed tab

Or from the user app you can do it from
Other Actions > Staff Directory > Edit Staff > and update Geofencing locations