Well, he lived in Dublin, where Stoker lived, and I'd bet the library he visited had a special Stoker collection that might have attracted a fan. There's also the fact that Stoker's mother Charlotte helped open state schools for deaf children; so there may have been some connection there, too. But yeah, on such strange coincidences many discoveries rest.
It's interesting how much you can find just by reading old newspapers and magazines. Everybody just reads Wikipedia now, even journalists, so it's become basically the sole source of truth. If it's not in there, it's not on record. But if you scratch the surface just a little bit, you find tidbits that are only mentioned on places like ancient newsgroup threads, or sometimes not mentioned at all on the public web. Libraries, man!