The rock slab in the center section also has a tendency to come out and bounce around the trailer ....
Is there really any value to the center section of the sofa as seating?
After playing for a year, our answer was - nope / no value. We never used it as seating. It's to small for anything other than a kid. Sitting there is not very comfortable at all. Indeed our answer may not be your answer
Once that was decided, the center section comes out by loosening a couple of nuts (two in front and *maybe* one in back ( = ours did not have a nut in back). It lifts out and can be stored away.
You now have a nice open space between the two recliners to build up whatever sort of storage gizmo your heart desires. Ours got made from plywood and a ton of 3D printed parts. It works of us, but likely for nobody else on the planet. There are lots of ways you could do it up.