I am in the process of installing the small Sieka 24" that was original equipment in the overhead bunk area of my Four Winds 22e. I replaced it with a Visio 32", but back to your original question. My install is against the refer cabinet at the foot of the bed. Same problem with nothing more that a thin panel wall with no other support. I am looking at a possibility which should work.
The idea is to spread the load across the thin panel. I have a nice piece of 3/4"red oak about 10" by 12". and the idea is to stain and finish it. Then mount it to the thin paneling by bonding and screws. It will be hidden by the TV anyway so it really does not need to be furniture quality. Mount the TV to a simple tilt only mount, not a swing arm, too much downward stress to the paneling when the arm is extended. Anyhow, it's one solution.
__________________
|