what's this disease?

[geogeo21]

i'm wondering what kind of disease this is. they were healthy when I got them and repotted them. the soil was decomposed with a lot of rotted roots. after repotting, a couple of weeks later they started to become brown. at first I thought it might be from the acclimation from being grown under lights to getting real sun. I do have them outside. during the days it's an average of 75deg with night time an average of 55deg. my other orchids are perfectly fine and thriving. the one orchid is paph lantha stage the other is paph limerick. I have them growing with cats. i know this summer, i had that brown rust that attacked all of my snap dragons. so im hoping that this is not it.