It looks like it's too dry to me. My Onc love to be watered and suck water like there's no tomorrow...that's why I used S/H for my Onc. White Onc roots are good, but what do you mean by "broken?"
It could be that the plant is stressed from being repotted so much...keep it in a south facing window and monitor the watering and ease up on the fertilizer- weakly, weekly...and just let it rest...no repotting or moving. Orchids can sometimes take a few weeks/months to get used to a new growing situation. Next time you over-fertilize, flush the moss with clear water while the plant is still in it's current pot-rather than repotting...this might keep it from "stressing." Onc roots are very fragle so the less movement they have the better...
(i've included pictures of one of my Onc that is very happy- lots of new growth and reblooming to let you know what a healthy plant looks like) I'm no expert grower, but I say lay off the repotting, use a south facing window, water as frequently as the plant needs rather than on a schedule, and then wait- the plant will eventually recover.
Onc are hardly little buggers.
