Man that is going to be a tough one. As far as I know you can only have one BTN per PRI circuit max. One possibility, long shot, do you think that the TELCO could control the names if you went to account codes from the carrier? This way anyone that called from any phone on the network could enter their pin, or you insert the pin, and the carrier would be able to assign the call to the correct billing. Just a wild thought.
