You can try a slightly different approach and achieve similar results. Basically, RadGridView uses DataitemCollection, which is Telerik's alternative to the .net itemsCollection, which uses a QueryableCollectionView to add IQueryableSupport. So that, if you bind RadDataForm's ItemsSource directly to RadGridVIew's Items property, RadDataForm will use RadGridView's QCV internally, instead of creating a new one and you will have synchronization. I am attaching a simple demo project.
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