Your Phal orchid is in deep distress and will probably die. The one remaining leaf going yellow is not a good sign.

Here is a link to the American Orchid Society Phalaenopsis notes.

AOS Phalaenopsis notes

Arthur is more optimistic than I am. I don't think it's in distress ... it's dry as a bone and already dead.

Agreed. That plant is toast. Time for the compost bin or the fireplace :(

Unfortunately, your phal is not likely to pull through. Sometimes when plants are in deep distress they throw out a flower or two as a last attempt to propagate before death. The plant uses whatever energy it has left to to this. This is likely the case for yours. Plants die on all growers and we just get another one or three. And try again. Good luck

Throw it out. Deader than Carrot Top's career.