Immediately after the line
oFooter.Range.Fields.Update
put
UpdateAllFields
and add the following macro to the module, and all the fields in the doocument will be updated

Private Sub UpdateAllFields()
Dim oStory As Range
    For Each oStory In ActiveDocument.StoryRanges
        oStory.Fields.Update
        If oStory.StoryType <> wdMainTextStory Then
            While Not (oStory.NextStoryRange Is Nothing)
                Set oStory = oStory.NextStoryRange
                oStory.Fields.Update
            Wend
        End If
    Next oStory
    Set oStory = Nothing
lbl_Exit:
    Exit Sub
End Sub