Navigation controller large title not collapsing on scroll from child controller

I have a view controller I present with a navigation controller, and its main content changes based on the data the app has. So if theres no data, I display an empty state screen, if there is data I display a table controller. The empty state and table view are both separate controllers and I add them as children when needed. This seems to not work well with iOS 11s large titles and search controllers to hide them on scrolling. I can't find any information about it either.

Here's my navigation item / bar setup

navigationItem.largeTitleDisplayMode = .automatic
        navigationController?.navigationBar.prefersLargeTitles = true
        navigationItem.title = NSLocalizedString("LISTS_TITLE", comment: "Lists")
        navigationItem.hidesSearchBarWhenScrolling = true

and this is my code for adding / removing child controllers

private func setContentViewController(_ viewController: UIViewController) {
        for child in childViewControllers {
            child.willMove(toParentViewController: nil)
            child.view.removeFromSuperview()
            child.removeFromParentViewController()
        }
        addChildViewController(viewController)
        let contentView = viewController.view!
        contentView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(contentView)
        view.bringSubview(toFront: contentView)
        viewController.didMove(toParentViewController: self)
        /
        var constraints = [NSLayoutConstraint]()
        constraints.append(contentView.leadingAnchor.constraint(equalTo: view.leadingAnchor))
        constraints.append(contentView.trailingAnchor.constraint(equalTo: view.trailingAnchor))
        constraints.append(contentView.topAnchor.constraint(equalTo: view.topAnchor))
        constraints.append(contentView.bottomAnchor.constraint(equalTo: view.bottomAnchor))
        view.addConstraints(constraints)
}

If anyone has seen this as well, I'd apprechiate the help.