Sick phalaenopsis losing leaves

[bwehr28]

Helll all! I have tried searching this issue, but haven’t been able to find the answer here on the board. I rescued this Phal from a greenhouse near me that is closing. They said they had not watered the orchid in quite sometime. When I first got it, the leaves were soft and leathery. I soaked the orchid and inspected the roots. About 95% of the roots feel off when I took the orchid out of its original pot. I’ve reported in a coarse bark, charcoal, and perlite mix. I have a tray with gravel under the pot I keep water in and have been using a ziploc bag for increased humidity. The bag isn’t working out too great because if it stays too humid, white fuzzy hairs start to grown on the crown. I spray the roots with water every other day and do a soak once a week. The large leaves are dying and I am starting to get concerned. 1 leaf has already fallen off and the other is now tough and drying out. I fertilize with MSU mix weakly weekly. Am I watering too much or not enough? It’s in its original pot, but should I transplant to a smaller pot? Add finer potting media? I know the roots can photosynthesize, but there’s only 1! The keiki is growing so I’m happy with that. I’m attempting to attach pictures to show the orchid and it’s progress. Thank you all for all your help!