RE: speckled leather dying?
It isn't looking the best, but it is still partially polyped out. I have a huge one like it. Try moving it up in the tank. Mine is right at the top and loves high light. If it continues to 'melt' at the base, might try fragging the decaying flesh and making two or three smaller corals. It usually takes mine a few weeks to attach when I frag it.
HTH.
Ed
Custom Acrylic 180g RR, acrylic sump, 45BR frag tank, 18g fuge, 250+/- lbs LR, Euro Reef CS8-2, 10x39W T5, softies, LPS, and a few SPS.