The pet barrier can be seen below:

However, after installing the pet barrier, my crafty little meagle has managed to stick her head under the lowest horizontal rod of the barrier and then lift her head up, which expands the gap enough to climb over the back seat. This is all due to the fact that my rear headrests are not "locking" into the notched positions when raised. After looking at the headrests, it actually appears as though the notches in the headrest posts may be on the wrong side (i.e., opposite of the release) of the post, which would make it impossible for it to latch at all. If that's not the reason, the latch/notch mechanism is simply too weak to prevent the headrest from moving.
Has anyone experienced this? I know the headrests are facing the correct way, but the latch is simply ineffective. Without being able to secure the barrier by preventing the headrests from raising and lowering, she's not going to be able to enjoy car rides for awhile.
I would run the car by a dealership, but I purchased the car 5 hours away and the nearest Nissan dealership is over 30 minutes from home. I'm hoping there is a simple explanation or fix, but I'm at a loss.
Thanks in advance!

