Don K.- matches Brandon at FTDNA on chr. 4. Also matches Tiffany at FTDNA and Geni. He doesn't show as a match at FTDNA to me or Sandra although we overlap with Tiff and Brandon in that segment.
Geni reports he is our 16th cousin 5 times removed. This is a bit farther than one would hope with a 8.5 cM match. As well, Geni's path goes through our maternal grandfather. Most likely this match goes through our maternal grandmother, as there is no match with our maternal grandfather. For now, this one goes on the unsolved pile.