Negotiating emergency room bill as a foreigner?

My friend is visiting the US and got drugged at the club. He would have died if he hadn’t received emergency treatment. He was sent to the ER in an ambulance and stayed for 20 hours. He doesn’t have travelers insurance and will be discharged soon. Any advice on how to negotiate the bill would be greatly appreciated. At this point, all we know is to ask for an itemized bill.