Lou Sneary in big troubl - help needed

[Phyrex]

I was very happy to reflower this plant but what I found this morning did not make me very happy. I saw that one of the 2 flowers that were left, after I had accidentally sprayed the plant with fertilized water, had wilted already and had fallen of the spike. Then, I saw the worst thing ever. One leaf had fallen off and when I checked the others they fell of with the slightest touch. I'm assuming it's black rot which could put my whole collection in danger. I separated from the rest of the plants as soon as I saw it this morning but you can see form the pictures that the last two leaves are still properly attached. My two worries are this:

1. What can I do to prevent this from spreading to the rest of my collection if it hasn't yet done so; or how can I stop it if it has spread already???
2. Can I still save this plant??