Wpf: clipboardcontentbinding does not work for advanced datagrid-columns

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C#

DataTemplate

DataGrid

I am trying to export my DataGrid (name: myDataGrid) to .csv - but have ran into some issues. <Textcolumn> export as intended, but my <Datatemplate> <ComboBox> and <wpftool:datetimepicker> do not. Their cells end up empty.

Here's the XAML for the two columns:

<DataGridTemplateColumn>
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
             <wpfTool:DateTimePicker Value="{Binding PropertyName}"></wpfTool:DateTimePicker>
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

<DataGridTemplateColumn>
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <ComboBox SelectedValuePath="{Binding ExampleName, UpdateSourceTrigger=PropertyChanged}">
                <ComboBoxItem Content="25" Tag="0" />
                <ComboBoxItem Content="15" Tag="1" />
                <ComboBoxItem Content="12" Tag="2" />
                <ComboBoxItem Content="6" Tag="3" />
            </ComboBox>
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

And my "ExportToCSV"-method:

myDataGrid.SelectAllCells();
myDataGrid.ClipboardCopyMode = DataGridClipboardCopyMode.IncludeHeader;
ApplicationCommands.Copy.Execute(null, myDataGrid);
string result1 = (string)Clipboard.GetData(DataFormats.CommaSeparatedValue);
string result2 = (string)Clipboard.GetData(DataFormats.Text);
myDataGrid.UnselectAllCells();
System.IO.StreamWriter file1 = new("My:\File\Path\test.xls");
file1.WriteLine(result2.Replace(',', ' '));
file1.Close();

What I have tried:

I have been trying to set up the ClipboardContentBinding event, but could not get it working. I am using MVVM, but would be fine with a code behind solution as well.

I was not able to implement the solution provided in the accepted answer at Bind ClipboardContentBinding to DisplayMemberPath[^]