Resource 1 works, 2 doesn't - wpf

Question

<ToggleButton Command="{Binding Path=Command}" Content="{Binding Path=DisplayName}" Template="{Utilities:BindableResource {Binding Path=TemplateResource}}">
<ToggleButton.Style>
<Style TargetType="ToggleButton">
<Style.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Template" Value="{Utilities:BindableResource {Binding Path=SelectedTemplateResource}}" />
</Trigger>
</Style.Triggers>
</Style>
</ToggleButton.Style>
</ToggleButton>
The first bindable resource works for "TemplateResource" on the template property of togglebutton however "SelectedTemplateResource" does not work within the tiggers setter. This code is within a resourcedictionary where the actual resource is within a themed resourcedictionary.
I get an error saying key is null for xamlparseexception for the setter value. I've been stairing at this for hours but cannot figure out why it doesn't work... If I take out the style and replace the first binding with the second resource it does display proper however the binding within the style will not work.
Does anybody have any idea why?
EDIT
I just tried this but no luck.
<ToggleButton Command="{Binding Path=Command}" Content="{Binding Path=DisplayName}">
<ToggleButton.Style>
<Style TargetType="ToggleButton">
<Style.Triggers>
<Trigger Property="IsChecked" Value="False">
<Setter Property="Template" Value="{Utilities:BindableResource {Binding Path=TemplateResource}}" />
</Trigger>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Template" Value="{Utilities:BindableResource {Binding Path=SelectedTemplateResource}}" />
</Trigger>
</Style.Triggers>
</Style>
</ToggleButton.Style>
</ToggleButton>

Answer 1

After finding out this really is not possible to do in pure xaml I brought out the c# and create a custom control... this is very basic and can be improved on and I will have change a bit of it but ultimately a custom control solves the issue so that you can hit the click event from within the resource dictionary and change the template on the fly.
public class TabButton : Button
{
public static readonly DependencyProperty SelectedTemplateProperty =
DependencyProperty.Register("SelectedTemplate", typeof(ControlTemplate), typeof(TabButton));
public ControlTemplate SelectedTemplate
{
get { return base.GetValue(SelectedTemplateProperty) as ControlTemplate; }
set { base.SetValue(SelectedTemplateProperty, value); }
}
public TabButton()
{
this.Click += new RoutedEventHandler(TabButton_Click);
}
~TabButton()
{
}
public void TabButton_Click(object sender, RoutedEventArgs e)
{
ControlTemplate template = (ControlTemplate)this.FindResource("Environmental Template Selected");
(sender as TabButton).Template = template;
}
}
Cheers.