To me, it is a bit fishy as he should have informed the mother and / or the parents and than, your teenage daughter and than, do the exam, with their permission . Nowaday, you do not need a female present to do breast exams but the mother or parents should have been informed of it and a consent is needed.
I am a special therapist and I do breast exams with the therapies but I inform my patients / clients of it and never did anyone informed me that they did not want to. When I do therapy on a teenager, the mother and / or the parent is informed that I will be doing breast exam and none have told me no.
You should check this further.