Word is that he thought after playing during the stretch run and the playoffs in the AHL that he had earned a spot in the AHL. When he was sent to Wheeling of the ECHL during training camp, he had a meeting with the coach where he allegedly let him know how he felt about the reassignment. Rumor has it he stormed out of the office and slammed the door.
If all of this is true, then he may have been labeled as a bad attitude guy. You've seen the type of hard-working players that Shero prefers and that adds up to him being forgotten about when other ECHL d-men have gotten the call to Wilkes-Barre.
Since Pittsburgh owns his rights, he can't even accept a PTO with another AHL team if they would offer him the chance to play.