Sorry about the quality but that's it, the brown stuff is just coco fiber stuck to it. It's much smaller than the mouse was to begin with and seams to be mostly digested. My dad is going to sterilize the tank while she is at the vet and I'm going to set it back up the way it was for QT with paper towels and plastic hides before she goes back in. I just put up a piece of cardboard on the front so she has black out on all 4 sides now. All her temps and humidity are still stable and she has fresh water from this morning. Thanks for the help everyone and I will let you know what it is and what the vet says as soon as I can.