Actually, you and I are saying the same thing. BC/BS (or just plain
BS) is using this old excuse to increase their profits and are counting
on folks not doing anything about it. Further, even if they reverse
themselves later, they've still made money (presumably) on their
investments while the discussion is ongoing.
It might be interesting to ask to see the contract of the people whose
charges were denied and see if it actually says that they don't pay
non-mental health providers for legitimate diagnostic codes. It might
also be interesting to have them put in writing their reasons for
denying payments. The family could take that information to the HR
person at the company who bought the policy and tell them that BC/BS is
going to cost the purchaser more because they are not efficiently
using the premiums of their customers.
The company who purchased the insurance is the customer, not the
family. They have the leverage.