The same cover broke on my 2011 driver door after slamming it shut. That cover was a bit wobbly, and after a few days of driving my door came unlatched at 60mph! I pulled the door closed from inside but the door card was pulling off of the door! I had to roll the window down and reach out to the door handle and hold the door shut-ish while I pulled over.
The lock cover had almost fallen off, and somehow pulled the door handle open too. Easy enough to "fix" and continue on my day.
I figured I could just take off the cover trim piece and replace it later. Nope! It's the only thing holding the lock cylinder in! Without that piece, the lock can just fall out on the road and I don't want to imagine how much it would cost to get a replacement or re-key the car.
I'm looking into replacing mine now of course. Any tips appreciated.