Hi boothbay-
It is good that you repotted it. Hopefully, you cut off all those nasty, rotted roots. You might have to sacrifice the potential blooms and cut off the flower spike all the way.

Of course there are several ways to go about reviving your phal. My suggestion would be to use all new potting mix, including the sphag moss. I would use pretty small pot, especially if the rot system is nonexistent. After repotting, you may want to restrict watering for a couple of days. You definitely don't want to fertilize it until the root system is healthy again. Using fertilizer on unhealthy orchid will do more damage than good. When the roots are not healthy, they cannot absorb the fertilizer. Then the fertilizer will build up in the pot and the salts from it will lead to more dehydration. So you may want to hold up in the fertilizer. I would suggest putting the plant in a high humidity environment. I use an empty aquarium with moist sphag moss in the bottom for my recovery area. Also you may want to keep the plant in a shaded area (diffused light) for a couple of weeks. Hopefully the roots will come back soon.