I am with Hollylee and Sheridan.
It is very common for phals to experience root rot if planted in tightly packed moss. not your fault, though, they are usually overwatered before you buy them, been there, done that.
I too have had to "peel off" the remaining of an old phal leave, I did it carefully with sanitized tweezers. as for your roots, half of them look decent to me, cut back all the hollow ones, rinse with Listerine (as suggested by Sheridan) or hydro peroxide and repot, I use a mix of bark, LECE and a loose layer of moss on top. Keep in a warm and shady place and hold back on the watering for a couple of weeks.
PS Remember to pre-soak the potting mix 24-48 hrs before repotting