Xamarin.Forms map custom renderer example with an MVVM pattern

I followed the example here https://developer.xamarin.com/guides/xamarin-forms/application-fundamentals/custom-renderer/map/customized-pin/
And looked at the example code here https://developer.xamarin.com/samples/xamarin-forms/CustomRenderers/Map/Pin/

Problem is that I am using an MVVM pattern and it seems that this example will not work with code anywhere but in the code behind...

What am I missing here ?

I have tried to bind the CustomPins to a a list in the view model that is the binding context of the page but it does not see them.

I try to bind the position to a view model position and it navigates to Rome (I am using 40.628836,-79.170909)

Any help is appreciated