Hmmm. Neodesha's don't have very many spots to injure oneself on. Perhaps between the litter dam and the glass? About the only place I can even come close to thinking. If she is persistent enough, and keeps trying to wedge herself into the crack, it could cause some abrasions. Just a stab in the dark though.
Check her out after her next shed, and see if it is still discolored. Aurora was pushing so hard against the glass, she caused what looked like a blood blister on her nose. (looked normal except the discoloring) Of course, she later rubbed it completely OFF, so now it's a scab.
Is this a new arrival, or did this happen while in your care? Maybe she came like that?