Your best bet is not use the thin walls to support anything. The screws may just pull through. What most folks do is mount a back board up first and mount their TV Mount to the large board. something like this from google...
You might want to look at the area they recommend and see if maybe they have a large one-inch thick back board behind the thin wall.
I would use MOLLY BOLTs to mount the back board if you can't get both ends into the small studs...
This is what a molly bolt looks like...
Then you can use regular wood screws to go into the back board to secure the HDTV mount.
finished product might look something like this
just my thoughts
Roy Ken
