| Boy that looks bad. I don't have experience with those types of orchids but I do sometimes get rot on my Cymbidium bulbs. The best thing is to remove all signs of rot ASAP and disinfect the plant and repot. I would cut the whole bulb to be safe. Usually the rot comes from below and the bulb is infected already.
That's my opinion but wait for more expert advice from the others.
__________________  Solay  |