What is the significance of the name Unlick Norman Owen and why is the name appropriate for the circumstances?

In Chapter One, each of the guestd tells their own story of how they were contacted in some way, asking them to arrive at the Island on this particular date. Mr. Rogers fetches the letter that instructed him to play the record. It is from the Ritz Hotel, typed, and signed Ulick Norman Owen. Others tell of how they were contacted by old friends, all of whom they were not able to be in touch with, asking them to come. Mr. Blore lies and tells them the same, but Mr. Justice Wargrave and Lombard call him out on his lie. They note that the voice had not mentioned a “Mr. Davis,” but rather a Mr. Blore. Blore confesses that he is a detective, and Mr. Owens had hired him to watch and observe each of the guests. Now he doubts that Mr. Owens even exists. Wargrave strokes his upper lip, his tell of deep thinking, as he notes that the initials of Mr. Owen are “U.N. Own. Or by a light stretch of fancy, UNKNOWN!” The judge tells the guests that he believes that some “dangerous homicidal lunatic” has summoned them to this island.