I've continued to write back that I think the hotel should honor the originally quoted rate and haven't seen my bookings change from the $10/day yet. Just received an email from them:
Thank you for contacting Booking.com, we apologise for any inconvenience this issue may have caused.
At Booking.com we take all of our customers concerns seriously. Please allow us 7 days to fully investigate your complaint. We have contacted Holiday Inn Resort Baruna Bali directly, and hope to find a satisfactory conclusion as soon as possible.
We will keep you informed of any new developments.
Once again thank you for contacting Booking.com. We will do our best to help resolve this issue as quickly as possible.
Kind regards,