Uh...hell no, 'new' has nothing to do with it.
This is old school 'Blues' behavior from way back (yes....I have been on the IT side of health insurance and TPAs for north of 20years)
The Blues were the biggest boys on the block for a lot of years. They were also one of the few who would write individual policies for those without company coverage for ages.
They are accustomed to getting providers - particularly institutional providers - to bow to their bidding. They are also accustomed to the consumer having no recourse but to take their crap.
If anything, a wider market dilutes their power AND the risk balancing from the exchanges should substantially decrease this kind of behavior.
I also doubt his coverage is through ACA. What I expect is that you have a case manager under a incentive plan that pays him for meeting certain 'guidelines' of care and keeps inpatient days below their threshold. The Blues are one of the last companies to pay this way. Aetna does not. Also, the HEDIS incentives inside ACA would actually penalize a pattern of behavior like that.
The cases manager is an asshole. The person with the POA should ask for another one. Immediately.