Your orchid media looks to have had it. It is turning more into soil than bark. You are probably slowly drowning the Catt. That's where you start.....replace the media with a good orchid mix. I am not sure you can get that plant/roots into a 4" pot. You might need a 5". But after trimming all the dead tissue away, a 4" pot may be fine. I started using pretty much mesh-pots with all my orchids and seem to have good results. It certainly allows that media and roots to get more air than any other pot that I know of. Trim away all the dead roots before you repot. You may not find many viable roots but protect those as much as possible. That new pseudobulb may have a root or two attached, so look for that. You can also trim away any/all dead pseudobulbs. You might get some new growth from that/those cut areas. Sprinkle cinnamon on any cut area. It is a good, natural fungicide/bactericide.
Keep in mind, the vast majority of orchids need to dry out between watering, and Catt. are no exception to that rule. I don't know that the orchid is salvageable. I wish you luck, Heath.
