Hi all!

I am looking to book a night on the Caledonian Sleeper, but I am going to travel with a friend who does not have an interrail pass, he lives in the UK so it’s not a possibility sadly.
I asked their customer service what would be the best way to arrange this, and they said I can book a single room supplement just for me, but to tell the train crew before boarding that I have a second person traveling with me. They would then charge us an additional £50.

Does anyone have any experience with this? I don’t doubt what their support told me but it feels like a backdoor to save some costs, which I’ll gladly take of course.