Beginner Gardening: Brassia Verrucosa in bad condition, 1 by Sperovivo

Sperovivo wrote:
About a year ago I split my Brassia into two and the plants were fine and thriving until about a month ago. I admit I had been neglecting to water them every week but they were still green even though their psudobulbs had shrunk. I thought it would be a good idea to water them more(once a week) but they just turned yellow and started to lose their leaves. I thought they were looking better but then I went out of town and left them in the care of someone even less skilled and when I came back one of them was dead. I examined the remains and from what I gather it's root rot but I'm unsure; there were some tiny black spots that had been there since I got them;I just want to save my other one. Please take a look at the photo.