I have seen another case of self mutilation in leopard geckos and it was due to a wound being irritated (he kept opening up the wound and wouldn't let it heal). I am not sure what happened to said gecko, though

Has she had trouble shedding? Is there anything that may be irritating or skin or stressing her out? I know my enigmas get a little neurotic when stressed but I've never had one self mutilate before. Perhaps try darkening her enclosure (if it isn't already dark).

I would bump up the heat to 95 - 97F, you may see an increase in appetite.

I wish you the best with her