So far I had no issue at NUH with first pregnancy neither KKH for second pregnancy. However, if you are facing difficulties to pay, you may request to meet with Medical Social Worker and they will be able to assist you. For me during this period at KKH I did request partial payment and settling the bill before next appt. Subsequently, as soon as my MSW informed assistance is approved then no payment required for all my appt till for a period of time during this assistance.
In NUH, I do not face any financial issue, however, if there's delay, there's student doctor with the senior, they seek permission from patient to be with them for understudy. To which bill payment will be waived.
Perhaps maybe you can tell the counter pertaining yout conversation with the staff you spoke with and then you can proceed with appt.
itsallabout_mytwokids