I just wanted to mention that I had something similar infect one of my best paph divisions. I cut off diseased tissue (ouch) with sterilized instrument and sprayed twice with Dithane (a systemic-you can find it on the web) at a one-week interval and that was that. Mixing directions on the label. I don't like using chemicals, and do so rarely, but if one of my best plants is being threatened, I don't fool around with home remedies.

P.S. For a spreader-sticker, you can use a non-phosphorus dish-washing liquid at about 1/4 tsp / pint. I use Ivory.

HTH,

John