Rust? Spider Mites?

[Lagoon]

To me it doesn't look like spider damage, could be bark dust? I know media gets on my plants after a repot.

Just give it a good rinse down and see if the colour returns within a few days.
The catt looks very tired and drawn out, needs time to recoup.
I would pot it back up and give it some good strong lighting, just unpotting it will cause further stress.

Good luck