Creating a Simple Space Partitioning Algorithm Using TOctree

This documentation claims the AddElement method returns an ID https://docs.unrealengine.com/latest/INT/API/Runtime/Engine/TOctree/AddElement/index.html

But it’s a void method that appears to return nothing. Have I missed something or is the documentation lying to me? How can I get an ID after adding an octree element?

Thanks,

Brenden