Needing help/advice

[OrchidDelight]

I'm new to the orchid world and having an issue with one of my phals. I purchased it from a local nursery and while in the quarantine stage I noticed that it had mealy bugs. I unpotted the orchid removed all mealy bugs in sight and covered the orchid in alcohol. I repoted it in new medium and just kept an eye on it.

About two days later I noticed the bottom two leaves were turning yellow and wilting. When inspecting it I saw what I thought was more mealy bug cotton looking substance near the crown. But now I'm thinking it may have been fungus.

I've unpotted the orchid again removed the dead leaves and noticed half my roots have died. I've removed a lot of the root that I know are dead. The ones left still have dark spots on some.

I don't know what I'm dealing with should I cut any root the has dark spots on it? I've sprayed it in hydrogen peroxide. But I'm lost what to do next. I don't know if it's fungus, crown rot or root rot ?!?!?

I've attached pictures of my plant and would welcome any advice you can give. Thank you