Sounds to me the real issue is in how to set up functional attachment points and whether the structure of the frame is substantial enough to withstand the stresses imposed. If those issues can be solved, then having shocks on the trailer probably wouldn't hurt anything.
We travel on forest service roads from time to time and really haven't had a problem bouncing the trailer. But we're in no hurry, so we just go slowly over the bumps. ....makes the ride in the truck more comfortable too. But trucks tend to have stiffer suspensions than a 4Runner which rides more like a car.
Personally, unless one is talking about real off roading and jeep trails, I don't think there is any reason you couldn't take your Pod on forest service roads, as long as you proceed with caution and don't try to go over things that can hang up on the axle or the hitch. You may need to disconnect the WDH torsion bars, but, then, trailer sway is rarely a problem when traveling at walking speeds.