OMG! how in the world did they cut her tongue? They had to know about it and then not to tell you and to charge you on top of it! It sounds like the groomer was picking or teasing your dog to to have had the scissors so close in front of the face to get the tongue to begin with and if it was an accident - why didn't they pull away? That would be my first reaction! If it had been theirs - they wouldn't have gotten her tongue. Sounds like a simple lawsuit. They will settle before it goes to court due to cost and especially when they know they were in the wrong. Normally I would be the nice one and say forget about it - but for them (groomer) to know she didn;t and not say anything first! Wrong!! I hope your baby gets better.
T.