Jumping on what Sasha already said:
1) The courts don't really care what your daughter thinks and she won't really have a say-so in where she lives - it's above the reasoning skills of an 11yo anyway, so don't defer to her about it. You're the one in charge here and need to act like it.
2) What does DD11's counselor say about it? If she doesn't have one, get one.
3) Get a free consult with a lawyer who can tell you what to do and what is likely to happen in your court system in your circumstances.
3a) When you initiate court intervention in this -- and you will eventually -- request a guardian ad litem to investigate you and her and make a recommendation.
4) When I requested a guardian ad litem, my XAH was in the pink cloud of new recovery but the GAL was skeptical. So was I -- because his parents would hide his issues for him, it was extremely difficult to tell what was going on. He said XAH needed to show that he had completed six weeks of regular counseling, was attending an outpatient program, and could complete six weeks of drug testing, and then he could go back to regular unsupervised visits with DD8. I was livid because that seemed like SUCH a low bar to jump. But you know, in seven years, he never met that bar.
YMMV, but agreed with everyone above that you should stop forcing fantasy reconciliations. It's way too soon. No major changes for a year is a great rule - you'll learn a lot during that time and save yourself a huge number of headaches if you can maintain that boundary.