If she's not eating, you can tube feed her. @casportpony should be able to help you. I can't say whether it's better to try and save her or cull her. I wish I could help more. Kathy has been very helpful to me. Hopefully she can give you some instruction what to do.
I had a possum attack but unfortunately, they were killed. I would keep her there and see how she does over the next few days. Maybe someone else can give you more advice about what to do. She's very lucky to have survived this anyway. If she gets worse, it might be the best to cull her but if...