There is another post where it is assumed that the RS guide will take care of you in the event of a medical issue. It that is true or not you have to ask RS, but most on the forum travel more than just RS tours. So ......
You are an experienced traveler, so you and your husband didn’t leave home without travel medical and evacuation insurance.
Upon arriving in London, about 10am, your husband saw the prices and had a stroke and fell to the sidewalk. After a few minutes of listening to you screaming, someone called for an ambulance.
The ambulance driver a fine Scottish lad shouted out the name of the hospital and the ambulance sped away. Neither you, nor any of the English present at the site understood a word the Scotsman said.
SCENARIO A
Fortunately the med team stabilized your husband, but he remained unconscious. The nurses searched his pockets to determine who he was. They found a Texas drivers license, a photo copy of a passport, 22 euro (why euro?), an ATM and a credit card, an unmarked plastic room access card and a locked cell phone with a low battery. They have no one to contact so they just keep working on your husband and hope for the best. Sure, yuu signed up with the US State Deprtment and they have emergency contact information, but do you really think the doctor has the time to try and figure out who to call, or even knows that's an option?
You tried calling his phone, but he was in no shape to answer. You didn’t know what to do so you started to return to the hotel, but didn’t have the room key. In the $75 taxi ride you thought to call the US Consulate, but you didn’t know the number. Your phone didn’t have data (only your husband’s phone did to save $50 on the trip), so you would need the hotel Wi-Fi to get online and find the consulate number. At 11:45 you had the number and were making the call. Three transfers and 15 minutes on hold and you had a real person. “Sorry ma’am, you need to come to the consulate to file a report”. 1pm you are at the consulate. Now 3 hours after the incident began. Another 30 minutes of waiting, 30 minutes of paperwork then back to waiting. After an hour you are told that you husband was located. Now, 3pm and you are in another $75 taxi to the hospital. You arrive at 3:30pm. So for 5.5 hours you had no idea if he was even alive.
“Does your husband have private insurance,” you are asked. Yes, but the paperwork is “maybe” in the hotel in the luggage. You are told he will be fine but maybe should be taken home to the states if you have insurance for that…. You do, but not sure he ever printed it out. Somewhere in the email on his now dead phone.
SCENARIO B:
In addition to the Passport, ATM and credit card, room key card, and cash, the nurse found in your husbands pockets a card that said “IN EMERGENCY” which had your emergency contact information and called you immediately. There was also a QR code to a link to a cloud folder with all the insurance and additional emergency contact information in the event you could not be found. Even information on medications taken, conditions, doctors.
The nurse called you and then scanned the QR code and gave the information to the doctor.
In the event that was overlooked, the lock screen on his phone said: “In case of emergency or finding lost phone (50€ reward) call +1 999 555 1212” that being your phone number. Your phone’s start up screen has your husband’s phone number and you both have international service and data.
AND FOR SINGLE TRAVELERS: If you end up in the hospital for several months, who pays the mortgage, who pays the phone and electric bills, taxes, medical bills, medical insurance .... who calls your relatives and friends, where is the Will? Who can dictate your medical care if you can not? Thats another cloud folder and another QR code.