My 2 cents. Why not book a new ticket from Narita to SG and keep the Narita/BKK sectort open? You actually save 2 day.
Thank you for rhe suggestion. This is still an ppen option for me. Honestly I'm a little buying time and look see look see her condition and urgency. If not necessary to go Singapore and if Bumrungrag is still dry by 8th then I can save a trip.
Now in Haneda domestic terminal waiting.