After 50+ attempts, I finally got it to work. Here are the things I did:
1. Do Not Disturb
2. Airplane Mode with Do Not Disturb
3. Removing all notifications including persistent notification like weather and my watch connection.
4. Cover Display ON or Cover Display OFF
So at the end, I had Do Not Disturb, Airplane Mode, No Notifications, and Cover Display OFF. It still said it failed, but one more reboot and it took anyway. Now it says it is the latest. I thought there was supposed to be something about the Cover Display working in landscape mode, but it doesn't for me. However, I don't care about that, at least I have a External Display again and can answer the phone with the device closed. What an ordeal!