It Never Enter Our Minds.....(Advice Needed)

It never entered our minds that we would get a child that we did not like. Let me say, I realize our mistake. We didn't go into foster care to help children. We were always clear that we wanted to adopt. Our first placement is a sibling group of 4 kids. Their plan is adoption, TPR is scheduled. These children have been with over a year. The problem....the oldest child. She has behavior issues, very manipulative, bossy, and just (to us) is unpleasant. We have taken her to counseling and she got a PTSD diagnosis, however, because of financial reason (long story...Medicaid issue) we are unable to take her back to see that therapist. Oh, and all children are 5 and under. So this is the 5 year old who behaves badly. She is up and down, but she is always a problem, for me and my spouse. I have finally asked for her to be removed however that seems to have gone over the caseworkers head. This 5 year old is very bonded with one of my family members and this creates another situation. She is the source of constant conflict with me and this family member. I feel as though I'm always being told that I am "on her back" all the time, and that we "just don't like her". However, we are in a lose-lose situation. The problem is that we are bonded with the younger siblings. We want to adopt them. However, I don't want to screw the 5 year old up even more by separating her from them. But sending them all back would screw up the other kids. Either way we are made to feel like the bad guys in this. We really are crazy about the 3 younger kids but the oldest is making life unbearable. Do I sacrifice the other children so that the oldest doesn't lose the last remaining family members that she knows? Do I sign up for a life of misery by keeping all 4? Honestly, I don't feel she even wants to live at our house. She has told me that her siblings can stay with us and she can go somewhere else. But that is a 5 year old talking. I cannot give this child what she needs, and sometimes children just aren't a good fit. But if this child is raised by me, I fear she will turn out very badly. I think she needs a lot of counseling, which she can't get in my home. She doesn't respect me or my spouse, she doesn't listen or do anything we ask unless she feels like it. It's just a constant battle of wills. We have been offered intensive home therapy but that really doesn't fit into our schedule and life. Their are 3 other children in the home, they are all young and have developmental issues. We do not get home until the evening and by then it's dinner, bath, books and bed. After a year of begging for help (therapy) for this child, I really don't feel like I even want to at this point. I just don't know what to do anymore.