Repotted Phals due to root rot.

[Ravanna Lamia]

Hi there, l am a new caretaker of 3 Phal orchids.
1. Mizuki: recently bought and in perfect condition. Currently in full bloom with healthy roots.
2. Yona: Probably a few months old. No flowers or stems yet, recently repotted due to root rot but still had surviving roots and aerial roots.
3. Takeo: rescued orchid that had been planted into soil for a few months. Had no surviving roots but didn't give up hope as she had one small new leaf. Has been repotted and hope to see some improvement.

I repotted Yona and Takeo a few days ago. Have not seen any change in Takeo yet but have been keeping her medium moist to encourage root growth. Yona ( the one with roots) was also repotted into new medium. I am worried about her since it seems to me that the colour of her roots has changed can anyone tell me if she is fine or is there reason to worry.