I followed your directions but our BRAND NEW pacifica limited has a metal ring stopper" preventing the head restraint rods from exciting the seat. I'm not a mechanic so pardon the lack of correct terms. The metal ring stopper in a different color mental. I tried to use pliers and a wrench. No dice.
I wonder if they added that ring to keep folks from pulling them out. My van is an early build, so that may have been a revision. Can you photo the ring?