uncheck checkboxes in datatemplate wpf

I have 4 checkboxes in the datagrid I want to set ischecked = false them when a checkbox is activated Due to the use of datatemplate, I do not have access to the use of name controls
Using a sender, I can only access one control at a time But I want to turn off 3 checkboxes and activate a checkbox
this is my template:

 <DataGridTemplateColumn.CellTemplate>
                                        <DataTemplate>
                                            <StackPanel Orientation="Vertical" Margin="5" HorizontalAlignment="Right">
                                                <Metro:MetroSwitch Checked="chk_Checked" Tag="exc" Margin="0,2"  Name="chkExcelent">خیلی خوب</Metro:MetroSwitch>
                                                <Metro:MetroSwitch Checked="chk_Checked" Tag="good" Margin="0,2" Name="chkGood">خوب</Metro:MetroSwitch>
                                                <Metro:MetroSwitch Checked="chk_Checked" Tag="notbad" Margin="0,2" Name="chkNotBad">قابل قبول</Metro:MetroSwitch>
                                                <Metro:MetroSwitch Checked="chk_Checked" Tag="bad"  Name="chkBad">نیاز به تلاش بیشتر</Metro:MetroSwitch>
                                            </StackPanel>
                                        </DataTemplate>
                                    </DataGridTemplateColumn.CellTemplate>

and this is my sender

 private void chk_Checked(object sender, RoutedEventArgs e)
        {
            switch ((sender as Arthas.Controls.Metro.MetroSwitch).Tag.ToString())
            {
                case "exc": Console.WriteLine("exc"); break;
                case "good": Console.WriteLine("ggg"); break;
                case "notbad": Console.WriteLine("nb"); break;
                case "bad": Console.WriteLine("bad"); break;

            }
        }