iOS UISplitView and NavigationPage result in black screen

I have a UISplitView on iOS iPad, trying to split my navigation in two due to the design of the app I'm developing. I'm doing this:

    splitVC = new MySplitViewController();
    var outlineVC = new OutlineViewController(core.GetRoot());

    rightNC = new NavigationPage (outlineVC);
    leftNC = new NavigationPage (columnVC);

    UIViewController leftVC = leftNC.CreateViewController (), rightVC = rightNC.CreateViewController ();

    splitVC.ViewControllers = new UIViewController[] { leftVC, rightVC };

    window.RootViewController = splitVC;

splitVC is a UISplitViewController, outlineVC and columnVC are both ContentPages, and rightNC/leftNC are both NavigationPages. I have used the debugger and can see that all UIViewControllers being used are valid (have iOS Renderer references), yet when I run this on iPad it'll give me a black screen. What could I be doing wrong?