Foxface Question

I sold my foxface this morning and just got a call from the new owner that she swam around fine for a few hours but now she's completely black, tail down and nose straight up between 2 rocks.  I've seen her mottled when scared, that giraffe coloring but never pitch black.  She's in the tank with other tankmates from my tank and 3 baby damsels.

He said he doesn't think she's breathing but I told him if she was dead she wouldn't be perfectly still, she'd be flowing with the current.

Anyway, has anyone seen a foxface pitch black and in that position?

I've seen her vertical before but not black.  I told them to dim the lights and stay away from the tank and let her calm down, we'll see how she does.

Ive had them go black as well. Maybe it thinks its an ostrich?