WIth US passport and in Business should take 10 minutes or less to clear immigration. It's a very short walk to the hotel. On the return you can use the lounge before and after pre-check. The one after is small and crowded. No need to go to pre check to early in my experience. 45 minutes before ETD is perfectly fine. I've done even later but have GE with kids best err on the side of caution so maybe 60 minutes.