Need help. Sick finger leather

[Scavenger]

During my substrate fiasco that I posted in another post "Why not to discuss reefing with a 3 year old" my recently fragged leather lost his "scab" Today, I woke up to it completely limp on the substrate. There was a very bad odour coming from the tank. I picked out the sick leather and it clouded out gel, rotten pieces and some mucus. About 30-40% of his body had rotted away. Figuring him for dead, I took it to the kitchen and run some tap water over it as I wanted to have a look at it'd demise. Once under the running tap water, it perked up a bit. I cleaned off all the gunk and returned it to the tank but in as much flow as I could find. It stayed up for a bit, but is slowly drooping again. My question is, can I do anything to help him and is he a danger to my other tank inhabitants. I am running quite a bit of carbon in the filter for toxins and my skimmer is in over drive. What else should I do???

Here's a pic of the sick coral.