The baby was assigned a temporary health card number by the hospital. Do I use that one, or do I have to wait until the real health card is assigned? If the latter, how do I know when it gets it’s health card?
You can definitely submit the claim with the infant's temporary health card number.
Typically, the parents should register the baby's health card within the first month after the baby's birth. The MoH will pay with claim with current number IF the parents complete the registration promptly. Please note that the MoH can hold the claim up to 90 days and then reject the claim if the parents do not register the baby's health card in time. You will then have to contact the baby's parents to obtain the updated health card number in order to submit your claim.