我也遇到這問題，找過沒解，最後用 VBA 解。
將 "合併儲存" 的資料寫一份到 另一列 .... 分開
既然寫 VBA 那就不必寫 "M行判斷式" ...直接將資訊寫到 M 就好了
以下是我亂搞寫的 ....沒有debug
還可再改精簡點 ....改天再改 .... XD

Sub test()
lr = Cells(1, 6).End(xlDown).Row
B = 0
For xl = 2 To lr
        If Cells(xl, 7).MergeCells = True Then
            If Not (Cells(xl, 7).Value = "") Then
                B = 0
            End If
            If Cells(xl - B, 7).Value = "DOG" Then
                Cells(xl, 13).Value = "V"
                B = B + 1
            Else
                Cells(xl, 13).Value = "X"
                B = B + 1
            End If
        ElseIf Cells(xl, 7).Value = "DOG" Then
            Cells(xl, 13).Value = "V"
            B = 0
        ElseIf Not (Cells(xl, 7).Value = "DOG") Then
            Cells(xl, 13).Value = "X"
            B = 0
        End If
 Next xl
End Sub

其他的慢慢改吧 .....