I was not able to reproduce your results in PI ProcessBook 2014. When I set the current context based on your code above, e.g.
Application.ContextHandlers("E").CurrentContext(ThisDisplay) = "\\DNG-AF2014\NuGreen\NuGreen\Houston" Application.ContextHandlers("E").CurrentContext(ThisDisplay) = "\\DNG-AF2014\NuGreen\NuGreen\Tucson"
The element relative display addin simply updates the context to the selected context. The tree also does not collapse.
Can you double check that path is correct (you can right click the element in the element relative display addin and select "copy path")? Can you also provide us with some screenshots to further understand your issue?
Thank you Daphne,
in this moment I don't have 2014 or 2015 installed. As soon as I can try it, I will let you know.