Card IO crashes on iOS 13

Question

I'm trying to get Card IO to work on iOS 13 using the provided view controller. Unfortunately, I'm seeing a crash when I go to open the view controller in _platform_strlen. Why am I getting a crash there and how can I avoid it? Note: I'm calling this when a user pushes a button.

Here is the relevant code:

override func viewDidLoad() {
    super.viewDidLoad()
    ...
    CardIOUtilities.preload()
}

@IBAction func scanCardAction(_ sender: Any) {
    if let cardIOVC = CardIOPaymentViewController(paymentDelegate: self) {
        cardIOVC.hideCardIOLogo = true
        present(cardIOVC, animated: true, completion: nil)
    }
}