Season 11 Episode 19

When Lydia, Aaron and Jerry were inside a building, and the place is fully swarmed by walkers, they notice the Doorknob moving. And Jerry yells,

"What the hell? Since when do the dead use frickin' doorknobs?!"

And for which Aaron says "Whisperers"

But in the pilot episode, we can see that Morgen's wife trying the open the door using doorknob after turning into a walker. Did they forget that totally? Has anyone else noticed this.