WPF dynamically change image source based on two values

Question

I'm new to WPF and I'm trying to show 2 versions of image depends on values in other Devexpress' gridcontrol columns.

I have gridcontrol which contains these columns:

                <dxg:GridColumn x:Name="iloscDoWydania" FieldName="IloscDoWydania" MinWidth="50" Width="50">
                <dxg:GridColumn.DisplayTemplate>
                    <dxg:DefaultControlTemplate>
                        <Label FontSize="20" FontWeight="SemiBold" Content="{Binding Path=RowData.Row.IloscDoWydania}"
                               HorizontalAlignment="Center" VerticalAlignment="Center"/>
                    </dxg:DefaultControlTemplate>
                </dxg:GridColumn.DisplayTemplate>
            </dxg:GridColumn>

            <dxg:GridColumn x:Name="iloscWydana" FieldName="IloscWydana" MinWidth="50" Width="50">
                <dxg:GridColumn.DisplayTemplate>
                    <dxg:DefaultControlTemplate>
                        <Label FontSize="20" FontWeight="SemiBold" Content="{Binding Path=RowData.Row.IloscWydana}"
                               HorizontalAlignment="Center" VerticalAlignment="Center"/>
                    </dxg:DefaultControlTemplate>
                </dxg:GridColumn.DisplayTemplate>
            </dxg:GridColumn>

            <dxg:GridColumn x:Name="status" FieldName="Status" MinWidth="50" Width="50">
                <DataTemplate>
                    <Image>
                        <Image.Style>
                            <Style TargetType="{x:Type Image}">
                                <Setter Property="Source" Value="/WMS;component/Resources/Ok-48.png" />
                                <Style.Triggers>
                                    <DataTrigger Value="True" Binding="{Binding Path=RowData.Row.IloscWydana, 
                                                                        Converter={StaticResource ResourceKey=StatusConverter}, 
                                                                        ConverterParameter={Binding Path=RowData.RowIloscDoWydania}}">
                                        <Setter Property="Source" Value="/WMS;component/Resources/Cancel-48.png"/>
                                    </DataTrigger>
                                </Style.Triggers>
                            </Style>
                        </Image.Style>
                    </Image>
                </DataTemplate>
            </dxg:GridColumn>

I want to show "OK" image when value of IloscDoWydania column is less than IloscWydana.

Here is my converter class:

public class CustomStatusConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (System.Convert.ToInt32(value) < System.Convert.ToInt32(parameter))
            return true;
        else
            return false;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {

        return DependencyProperty.UnsetValue;
    }
}

Unfortunately my custom Convert method isn't firing.