I rescued two phals about 4 months ago and one looks very similar to your issue. The problem was that they had almost no light and were being watered, with an icecube, once a day.
I cut the leaves from where they were damaged and left one alone.
They spent a month in my general area and then went to my phal window. Both had next to no roots and are now growing leaves and roots.
The one I didn't cut I think is kind of starting over and sprouted a new growth as well.
