Christy is right, on some occasions an out of network provider will treat as IN network with special authorization. They do it on a case by case basis and it depends on the area of the provider, the type of provider, etc.
If the carrier is BCBS you will want to collect from the patient as they will only honor assignment of benefits from a participating provider. Otherwise you can use an AOB, have the patient pay their copay. Your authorization will actually spell this out. You will want to make sure you put in your authorization and record how many visits along with documetnation that they are authorizing at in network rate. A lot of EAP work this way, MAKE sure this is NOT an EAP.. If it is an EAP you want to be DOUBLY careful of documentation and make sure NO visits get billed to the major medical or TPA!! A lot of times bilers get these out of network authorizations and don't realize they are EAP sessions!