Another photo

From my experience when re-potting, it's always best to take it out of the plastic and put it into a ceramic pot with drainage holes. I received a Phal that was in major shock and almost died. Wilting, withering and yellowing leaves like you described. I re-potted it in a ceramic pot about 1/2 inch bigger then the plasic pot because orchids like to be snug. I cut off all the dead brown mushy roots that looked rotted and I cut the flower spike right off at the bottom so the plant can focus all it's energy and nutrients on forming new roots and the leaves and hoped for the best... As of today I got a ton of new roots and a brand new flower spike starting. The spike grew only 2 weeks after the re-potting. I don't use any orchid foods just bark and soil mix and lightly watering 2 times a week (Monday & Friday) and sit right next to a frosted glass window. My Phals are all in bloom all year around now and are loving life. I hope this helped.