I can understand your concern of the school not comparing apples to apples for ranking/grades. That said, many schools have this issue even without IB courses. Feels similar to schools that don’t weight honors and AP courses. Two students can have a 4.0 UW GPA but with extremely different course rigor.
Colleges adcoms WILL see the rigor. They know IB is more challenging. And your D will have the added benefit of being well prepared for college.
That said, if you live in TX and you need ranking for auto admit, I might rethink IB.