Dying phal, newb to orchids

[Falsk]

Hello everyone. I've put off registering/nagging you wonderful folks with my newbie questions with the hope I could figure out proper phal care on my own, but alas, such was not the case...

My ailing grandmother was given one of those Home Depot phals that was ultimately left on a windowsill to perish. Somehow I inherited back in May and began extensive researching into proper orchid care. I got into succulents a few years ago and am proud of the crowd I have, but orchids have always been too daunting. But I really wanted to give it a shot so I took it out of its little pot, pulled out the soaked spagnum, cut back the dried-out spike and cut away the dried roots (didn't know about sterilizing the cutting tool, so that's strike one...)

For a month or two it struggled. It started putting out a leaf that was all mottled and bumpy and didn't look healthy at all. About 6 weeks ago I fashioned a new container out of a water bottle (but didn't cut air holes for some dumb reason) and bought some orchid fertilizer (Jack's Classic 30-10-10) and put it in new bark I bought from Home Depot. For the last few weeks it started looking much better. The mottled leaf started growing much faster and smoothed out and another little leaf started growing. However, I think there was still humidity building inside the bottle (thanks to my forgetfulness with the air holes) and I noticed today white fuzzy mold (is it mold?) growing on a root and the stick it's tied to.

At this point I'm having trouble assessing with the problem is and what action I should take (if it's able to be saved at all). Again, sorry to nag. Any suggestions would be greatly appreciated. Spent all morning watching YouTube videos but I'm just at a loss with my particular problem. Attaching a bunch of close up photos to help. Thank you thank you thank you.