What about Bayle Doman? It is possible that he is (or was) connected with Sammy. Remember that Sammy tells Sevannah that he has something that controls male channelers. Bayle Doman has such a device, Nynaeve gave it to him to dump in the deepest part of the ocean that there was. So he could have given it to Sammy, and also he's an Illianer, so it would give him good reason to collect all of the old things that he could find. I'm not convinced that he is a DF, but it is an interesting possibility.