Just a quick note for US credit card-holding Bonvoy members who are thinking about booking this hotel or a hotel nearby:
The 1st floor restaurant ("Feast") is a hotel-owned restaurant. Just had a lunch buffet there a week ago without staying at the hotel. Showed them my membership QR code when I went up to the cashier to pay, and paid with my Ritz Carlton cc. Shown in my cc app as "Daewoo Hotel Songdo" but it got the 6x points eventually. Got about 1k points overall.