Great suggestions here but I have the opposite problem. I have a 15 year old that doesn't always like going to her dad's. I've asked her why and her reasons are that Dad is a little stricter than I am (usual story with one parent being stricter) also she doesn't always feel comfortable...like for instance her stepmum told her to make herself some lunch to take to work and DD just went into the kitchen and stook there and didn't know what to do. She didn't want to overstep boundaries and eat the wrong thing and didn't want to ask...so she didn't bother making her lunch at all. She's also told me that she finds it hard to say no to dad and hard to ask him for things like going out and stuff. Whereas with me...anything goes really. She finds me more reasonable and balanced whereas I think her dad still sees her as a little girl of sorts. She's maturing and maturing fast and he may not be keeping up.
Having said all that, unlike the BM in your situation, I have just said that she has to suck it up, because different people have different rules that's just life. She needs to work on more communication with her father if she feels she can't talk to him (I know the feeling though,...it's one of the reasons why he's my ex But I didn't tell her that).
So...things are mosying along as they are and probably will continue to until she moves out probably - which I can't see happening for quite a while.
All you can do is be there for her. At this stage really it's out of the judge's hands as her views are going to be heard but at the same time, judge's aren't stupid either and they'd know that sometimes teens like to have more 'freedom' to do what they want and would choose a parent over the other just for that reason sometimes. But I'd do what others have suggested, if it turns out that DSD chooses to not come round as often then just keep ringing and texting and inviting her to family things and keep her in the loop. One day she'll be a grown up and this is how your relationship will naturally evolve anyway