Edited to add: Jen, I was working on this post while you were posting the above. Here's just my two cents on the situation.
The cat site is a place for discussion and education.
85% of all cats surrendered to shelters for behavioral reasons are declawed. Declawed cats often bite because they no longer have claws. We are here at TCS to help people learn how to deal with their declawed cats. To help people learn how to deal with their crazy cats. To help people learn how to deal with their angry cats. To help people learn how to deal with their scared cats.
I cannot ever remember anyone ever having suggested that someone put down a cat for behavioral reasons.
Cuddles is declawed, and her world has just been turned upside down. Her territory is gone, her people are gone. She is in a strange place, with strange smells, with strange noises, with strange people, with other cats.
The one thing we write, over and over and over again in the ferals forum, when we try to help people with socializing feral rescues, you cannot work on any clock but the cat's: if things aren't going as expected, then the expections have to be changed. If things aren't going as we want - we simply have to forget what we want and focus on what the cat needs.
Rescue = patience, and that is the absolute key ingredient.
It seems to me this kitty simply needs more time. She seems (relatively) happy. She seems (relatively) loving.
Imagine a human child that had been confined to one home and never interacted with other human children. By the time that child was 12 or 24 years old - they would need a few years at least to learn how to appropriately interact with others.
Two months is simply not enough time.
When we rescue, we make a commitment. With the amount of money that we spent on Flowerbelle, Tuxedo, and the many other cats we've helped to keep alive, we could have started at least one, if not two, shelters. And we know how much that costs because we did finance the start-up of a no-kill shelter.
We became involved with and made the commitment to adopt a homeless 18 year old. She was a heroin addict. When she came off the heroin and we discovered that she is a manic depressive, bipolar, paranoid schitzophrenic, we did not halt the adoption process and take her back to the streets of Manhattan and dump her off because the money we were about to spend on her could better be spent on other children.
We don't euthanize our parents because in their failing health they have become inconvenient to us.
Either cats are disposable or they're not.
Rescuers shouldn't be part of the problem. If we all focused on the adoptable cats, what happens to those with special needs? What happens to those that TRULY need us?
Jen - I can understand the frustration. But this kitty needs you. I think that rather than posting in the S.O.S. forum, perhaps you should be posting in the Behavior forum to collect suggestions from people who may have new and interesting ideas about how to help this kitty.