No, when applying for the declaration of law you do not need to submit and therefore have any health insurance papers. However, it is the case that when you come to Curaçao on the basis of a granted declaration of law, you must be able to submit proof of health insurance.
When you want to come and live in Curaçao and you have deregistered in your country of origin, you can register with the SVB. This is the Social Insurance Bank where you can take out your health insurance. This is not mandatory, but then you are obliged to insure yourself elsewhere with coverage in Curaçao.