I have two XAML created working with the noesisVIew, however, I want to know how I would go about placing both of them in a scene and having one rendering behind the other.

I have tried with the render texture method, but im unsure of how I would place the unity UI behind the XAML UI.

Could solve this if im able to get NoesisGUI to Render over everything, so making it the first thing to render on the screen, rather then unity UI canvas.

You can use several cameras rendering to the same render target and using different depth values to precisely control the order of rendering. In one of the cameras you can render the Unity UI, in another Noesis, you could use another one for effects, etc.

It is briefly described in the Rendering section of the Unity tutorial.