A workaround I can think of could be adding custom labels and position them on the coordinates you would like to. Using this approach, would require you to disable the chart's AutoLayout. This is so because with AutoLayout se to True there won't be enough space available for the labels to be displayed and they may overlap your axis labels. You could set the AutoLayout to True, this however would require further chart's Appearance customizations.
Hope this helps.
the Telerik team
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