The torsion suspension systems don't need shocks, the older leaf spring trailers used shocks to control the bouncing that occurs over rough roads.
I had a 1971 AMC Hornet that had coil springs in front and leaf springs in the rear. As an experiment when replacing the shocks, I took the front shocks out and drove around the neighborhood. There wasn't a lot of difference with and without the front shocks, I could tell the front end was a little bouncier. Installed the new front shocks.
The did the same thing in the rear, removed the rear shocks and went for a test drive. The leaf springs had me bouncing all over, I went around the block and called it quits.
NOTE: the AMC Hornet did not use the shocks as a suspension component, only to control movement.
Shocks on a leaf sprung trailer will help keep the silverware in the drawer.
2002 35R Southwind, W22 8.1L Vortec UltraPower, 19.5' wheels
Toad: Wrangler, lifted and on 35" tires