IB is an excellent program. More than the program, what you get is an academic environment that is entirely and completely focused on academic achievement and college preparation.
It is not that IB is the 'secret sauce' it is the focus that comes with it. As an example, US News and World Report will publish an annual ranking of the top-100 public schools in America. For three of the last four years the top public school in America is Basis Charter High School in Phoenix, Arizona. Their entire curriculum pushes kids to prepare for, take and excel in AP courses. They do so well because it is the entire focus of the school.
If you had a chance for a rigorous, academically challenging environment (IB or AP) jump on it with two feet, fists, knees and elbows. It will benefit your daughter, her children, grandchildren, etc. Is will be one of the best decisions you could make over the next decade.
Just say'n!!