Had some young guests who commented there were no keys in the door locks. This was only the 2nd time in 3 years this has come up. Meantime I stayed in an AirBnB and noticed the review asked specifically if the rooms locked from the inside. I decided to find the keys for the 110 year old locks and ended up over-hauling one lock but simply cut a new key for the other room. Next guests from the same country immediately enquired about locking the bedroom doors. I said there were locks on the doors - whoopee, just in time! BUT somehow in making a key for the overhauled lock I had taken the re-cut key for the un-overhauled lock as a pattern for the overhaul and not replaced it in the old lock. Could I find that key? Of course not! It had vanished so I put in another older key and it worked just fine but being worn was a trifle loose. I said there was no need to lock the door in this country. At 3AM there was a knock on our bedroom door. “Excuse me but my friends cannot get out of their room and they need to go to the toilet” . Long stressful story short, the lock resisted all efforts to open it and they remained locked in until morning when I was able to remove the insect screens from the rather high up window and open the door from the inside with some wire. The old key had broken off! Everyone was very happy to escape and we had a big laugh about it but offered them dinner by way of thank you for being so good about the problem. Dinner seemed to go very well and we laughed and joked about the incident. They called me “Brother Graeme”, “Doorman” etc etc and we are invited to stay with them should we visit their country. So it does not always turn out bad if you have great guests like that. i have not seen the review yet!
I am not totally clear on your story, but if I read this correctly it could have been an extremely dangerous scenario with a horrific ending under different circumstances. All door locks should be able to work with a quick turn in case of fire or emergency, and should not require an exit key. This would be against our local code, and rightfully so.
I was confused as well. All doors should be able to unlock from the inside without a key. Please change your lock mechanisms asap