State v. Jerrell CJ, 283 Wis.2d 145 (2005) addressed this question in WI. There is not an automatic right to have a parent present, but the court can consider the police refusal to allow her to call a parent. Unfortunately, this would only help your daughter if she is charged with an offense. If she was really just a witness, then there might not be much you can do. A civil rights lawsuit is a possibility, but these are difficult to win and very expensive.
They do not have to honor her request to have a parent present. However, she can simply refuse to talk to them without a parent (or lawyer or whomever else she wants) there. They cannot make her talk. The only way to make someone talk is to subpoena them before the grand jury, and even then they can assert their 5th amendment right to remain silent.