The vet can definitely do more then any of us (as we're just over the internet obviously 😅) so that's great news! The vet will likely flush and debride it, and stitch the wound (if it isn't still infected). And probably give you antibiotics+painkillers, and that will make her feel loads better! 👍
From the picture it does still look a bit pink on the end. Clean it really good, then maybe try rubbing with coconut oil and slipping it back through the hole. Lather the wound good with antibiotic ointment too as the others said.
I helped someone with this when their duck tore underneath the bill and the tongue fell through. But it was almost immediately after...so I don't know if you can do anything here as it's dried. With the duck, we just pushed the tongue back through and closed the wound underneath, but I think...
Could it possibly be her tongue (that's dried hard)? I've seen cases where birds get a tear under their beaks and the tongue falls through and hardens.