If you have not already seen the information in link #1 about Coordination of Care Court for mentally ill juvenile offenders go there first and try the phone number at the bottom of the description.
http://www.utcourts.gov/courts/juv/juvsites/3rd/coord_care_court.html
Here are links to some info on holding options available in UT.
http://www.jjs.utah.gov/youth-services.htm
http://www.jjs.utah.gov/observe-assess.htm
Has a public defender been assigned to her or what? Whoever is her attorney (and I assume she has to have one if she's going in front of a judge) that is the first person I would be talking to about this. If the court appointed attorney isn't helpful/knowledgeable then you may need to hire an attorney yourself.
Here I was able to get a lot of help from a parent advocate for mental health hired by juvenile hall to help other parents. She gave me a lot of helpful info. I found her by accident when I called the medical clinic about my son's medications when he was being detained a couple weeks ago. So you could also call over there and ask if they have anything like that.
I would definitely try to get the psychiatrist to write a brief note saying how long he/she's been difficult child's doctor (if it's been a long time is really good) and that the intensive DBT program is what the psychiatrist is prescribing based on her significant clinical improvement while in the program.
Here, the juvenile hall psychiatrist was so completely out of left field it scared me. She met difficult child 2 for 20 minutes and told me he should come off all his medications and there was nothing wrong with him that couldn't be fixed with counseling and a lot of consequences (i.e. punishment). When I said well he was hospitalized for about 6 weeks total last spring and this was their diagnosis and his psychiatrist of 4 years who's seen him monthly for 4 years says the same - the juvie psychiatrist said, well I did only meet him for 20 minutes but I don't agree with them....
I made a point of telling the public defender about the difference of opinion between the juvie psychiatrist and our community psychiatrist - as in, we cannot let him stay in there if she has the power to change his treatment while he's there!!! The public defender brought it up in court and told the judge that there was a significant difference between the juvie psychiatrist and our community psychiatrist's treatment plan and that we wanted him released so he could be seen by his community psychiatrist. The judge actually asked how long difficult child 2 had been seeing the community doctor (4 years), who it was (she knew our psychiatrist by name) and when his next appointment was (the following day). It seemed to settle the question of his release to us once that issue was brought to the table.
My point is that don't assume too much. The judge may be more knowledgeable than you expect and the public defender may be helpful if you give that person the right info.
Good luck. Keep us posted.
Patricia