Carolina Medical Center is a private hospital and does not accept European Health Insurance Cards (EHIC), patients should first pay at the counter and then reclaim based on EU Directive 2011/24/EU1 on the application of patients’ rights in cross-border healthcare, which came into force on 24 April 2011. It was due to be transposed by Member States by 25 October 2013. It clarifies the rights of patients to seek reimbursement for healthcare received in another Member State.
Directive http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2011:088:0045:0065:EN:PDF
More information on EHIC card: https://www.schengenvisainfo.com/europe-health-insurance/ehic/