Sorry to hear about your Phal. Roots look quite bad but the leaves are good. I would not rule out a recovery at this stage.
1) Treat it with fungicide.
2) Treat it with a rooting harmone (seaweed extract/KLN) next
3) sphag and bag or glass jar with moist sphag. care the leaves don't touch the sides of the bag or jar.
hope for the best and it should recover. let us know how it goes