Address the problem and try and find a suitable solution. Try to ignore the terminology. You certainly have the right to ask to see all of that. If they didn't have those papers,, though, they wouldn't be open. You should not pause to ask for any credentials.
Most states have at least an annual inspection of a nursing home and a report is generated.
You should be able to get that report from the nursing home, but if they are defensive about it, the state Department of Health should provide that. Most of the better homes now also apply for and receive a National Certification from the Joint Commission on Healthcare Organizations. Don't be afraid to ask for your doctor's credentials, as well. Most nursing homes and physicians will display their licenses and accreditation s in a prominent place. The nutritional needs of the body really don't change that much as one ages.