You could use:
OLEFormat.Object.Application.Quit
Sub Test()
Dim s As InlineShape
For Each s In ActiveDocument.InlineShapes
With s
If .Type = wdInlineShapeEmbeddedOLEObject Then
If InStr(1, .OLEFormat.ProgID, "Excel") Then
.OLEFormat.Activate
.OLEFormat.Object.Application.Quit
End If
End If
End With
Next
End Sub
or
Sub Test()
Dim s As InlineShape
For Each s In ActiveDocument.InlineShapes
With s
If .Type = wdInlineShapeEmbeddedOLEObject Then
With .OLEFormat
If InStr(1, .ProgID, "Excel") Then
.Activate
.Object.Application.Quit
End If
End With
End If
End With
Next
End Sub