Solution 1:

Try wrapping your DataTemplate inside a UserControl like this -

<DataTemplate>
    <UserControl>
        <Grid>
            <VisualStateManager.VisualStateGroups>
            ...
        </Grid>
    </UserControl>
</DataTemplate>

Looks like any Control that has got a Content property will work. That's why UserControl works, so does a ContentControl.

So if you replace the UserControl with a ContentControl and give it an empty Style. It should work too.

<Style x:Key="EmptyContentControlStyle" TargetType="ContentControl">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ContentControl" />
        </Setter.Value>
    </Setter>
</Style>

<DataTemplate>
    <ContentControl Style="{StaticResource EmptyContentControlStyle}">
        <Grid>
            <VisualStateManager.VisualStateGroups>
            ...
        </Grid>
    </ContentControl>
</DataTemplate>