Who tells the story about the playhouse in 'Closing Time,' and what evidence is there that this person is the storyteller?

'Closing Time' is a story within a story. An unnamed narrator tells the reader about a club in London, where he and three other men stay late to tell ghost stories. This is the framing story, in which the ghost story is then told. When the ghost story begins to be told, it is not clear which person is telling the story. However, when the story has finished, both Paul and Martyn question the storyteller about various things in the story. The old man says nothing. As there are only four people, this strongly suggests that the story was told by the unnamed narrator of the framing