An emergency room at a hospital must treat him regardless of insurance. They may not be able to assume long term care but if he is in the ER and they order a scope at that time, he will get a scope.
Have you suggested that he apply for public aid? There are programs in place to help those who are uninsured. Next time he is in the ER ask to speak to the hospital's social worker who can help him start the paperwork. They might even be able to discuss the issues with the docs so he can receive additional services. You may need to go to a different hospital but don't give up and don't let your emotions interfer with those who can provide him care. Be his advocate without hostility. I don't have money and I am receiving quality care from the medical field.