@Twelfthman - you ask.
My training is in musical theatre and vocal performance as well. I have taught voice lessons for over 25 years. So, while it would be easier for me to hear/know problems in teaching, you can do this as well.
I suggest even asking schools if you and your daughter could sit quietly in on a couple of voice lessons or workshops with a voice teacher to see what both of you think of their training. I literally just said no to a school my daughter was considering after sitting in on a voice lesson at the school. The student had some quirky (and dangerous) tension issues going on, and when the teacher sung back to her, the teacher had the same issues. I spoke to my daughter’s classical teacher about this, and she had heard the same about the person as well…the exact same issues. That was enough.
So, ask to sit in on a lesson, and then ask around. See if professionals you know have heard of these people, and any feedback they may have. And judge for yourself.