What you share is definitely on my mind. I also think about my dog as both a liability but also her safety since she doesn't have a seat. We do have her attached to the van at least during any drives by connecting the two pillar tie down points to her harness.You have raised some very important questions within this above post.
In short the "What IF"?
Mounting the fridge is my biggest concern/liability if we do end up leaving it in the door. Right now the plan is to have it both through the floor as well as to the sidewall and connecting it to the bed structure to share some stress to the opposite side of the van. The remaining structure is all secured to the sidewall as well using 5/16 plus nuts. My wife was not excited about all the visible screws for the ceiling panels, but similarly, I don't want some loose plywood panels flying around if they're just glued on or screwed into some wood.
Maybe we need to wear our helmets when we drive