We did the fight twice, just to double check, and it was still happening then too, despite him succeeding on every save. Here is the logs entry of our first fight, note he gives no melee attacks in return while the pulse-spam is hitting him, but every reflex save succeeds (redacting AB/save values for purposes of player privacy):
how the ability is MEANT to work, is that the opponent avoids a stun if they succeed on their save when each bolt strikes:
