I wouldn't worry about them vetoing your doctor's recommendation; probably pretty unlikely. They probably say that because of patients who might be asking for it on their own without a doctor's actual input.

As far as the ER goes, if your husband is just so impatient that he won't sit in the ER with you, just tell him to drop you off with your suitcase and do it on your own. I've actually done that a couple of times and it was actually less stressful for me because I only had ME to deal with.