Canceled the hotel I booked in Seoul using Amex hotel credits. Decided it was too risky having to cancel and not being able to reuse the credit.
Booked the Hyatt Regency Lake Tahoe instead for $366/night. It's FHR, so booked 2 nights separately to use 2 credits. $45 resort fee payable at the hotel, but should be waived since DH is Globalist. $166 OOP is not bad. Even less if I factor in the $100 property credit, which we'll probably use at the restaurant.
I added in DH's Hyatt number when making the reservations and they showed up immediately in his account. Pleasantly surprised that it's so streamlined.