OMG! What a scary situation. Kim if it were me and you are able I would take what cats she has left and then stay away from her for awhile. If worse comes to worse and you were to be investigated I find it hard to believe that any fault could be found in your home. Your vet knows you and knows your kindness. Your cats are all healthy and well fed. What I can see from your pictures it looks like you have a beautiful home as well. I really don't think anything bad will happen to you. I think you just look like a loving person who has been trying to help out by fostering kittens for this woman. Anyone familiar with rescue work would not think you have too many cats. The director of our shelter has 20 cats of her own and is fostering another 24. I really don't see how they could do anything to you.
Are there ANY good rescue groups close even if they are not right in your immediate area? If you can find any in the phone book then call them. If you can find someone to talk to you may be able to get some advice or maybe even help.
My heart is breaking for you and the whole sad situation. It sounds like this S. started off with good intentions but became overwhelmed. It sure sounds like there is a desperate need for something in your area.
Prayers are on the way for you and all those lost animals. Let us know what you decide to do. I really think everything will be fine.