Hung. Meat it hung, humans are hanged. And that's an odd thing to do - assuming that the hanging room was separate from the larder, anyway (which would be the case in households prestigious enough to hold a shoot), there would be no reason to put a prepared item of food into a room which is less clean (given that it would contain unclean animal bodies in various states of de-composure) than the larder.

Strangely, I am perfectly aware that Edwardian cooks did not have blogs, however you appear to be unaware that information pre-dating the digital age is widely available online, and particularly in the case of a fashionable recipe, often quite well-researched. You also rushed to the conclusion that my own research was conducted exclusively on the internet.

It is hardly a stretch to imagine that some tv producer in the 90s decided to make up a back story for a fairly straightforward recipe in order to give it a bit of trendy glamour. Recipes are notorious for having apocryphal origin stories, after all. Calling that backstory in to question doesn't change the fact that it's an excellent sandwich.