Do you have a bracket kind of like this? Different trailer, but wouldn't surprise me if they used the same thing on some of the others. I had to tighten the screws on mine, they were only half way screwed in. Maybe you can find a similar bracket at the store and beef it up a bit? That wall isn't directly attached to the bracket at all, I'm assuming this is due to the flexing in my slide out, but if that's not a concern in your case, maybe screw the wall into the bracket so it's a bit sturdier if you can... probably what I'd do.
2016 27BHS Elite
2012 F-150 EcoBoost / Max Tow