One other thing- is there a screen/metal mesh top? Most ppl think sand boas don't climb, but I can remember a thread a long while back about one that kept doing just that, scraping against the screen top & falling. So if there's anything she can climb on, take it out. When snakes climb glass tanks, they jam themselves along the plastic molding at the top of the glass & against the screen to hold on. Check the upper edges for any rough or sharp spots & sand-file them down.
Oh my goodness I never even thought of that! Thats horrifying to think she could have done that. Poor thing. Ill do that right away!