Using the Vuforia EAGLView as a subview in an iOS app

I'm working on an app that may require the Vuforia AR view to be a subview of a UIView, allowing some native iOS elements to be seen and used at the bottom of the screen. I'm using Unity and I see that in the AppController.mm, in the        

"int OpenEAGL_UnityCallback(UIWindow** window, int* screenWidth, int* screenHeight,  int* openglesVersion)" method,

the EAGLView is a UIView and is a subview of the window "_window". It seems like the EAGLView could be made a subview of a UIView in another ViewController, but Unity makes "_window" full screen. I'd like to resize the EAGLView and display it on a ViewController with some iOS GUI elements. I've tried and either gotten Unity errors in the Xcode console or had the Unity view come up, apparently on top of the view I wanted it a subview of, and with very slow framrate. Before I spend hours trying to get this to work I would like to know it is even possible? Can I resize the Unity view and make it a subview of something in another viewcontroller? Thanks in advance for any help.