Like another user has pointed out, track rod (aka panhard bar) is displacing your axle by L*(cos(theta1)-cos(theta2)), where L is the track rod length, theta1 is the stock angle the track rod makes with the horizontal plane (should be close to 0), and theta2 is the new angle your track rod makes after the vehicle is lifted. Now you have static stress in the links because of the horizontal displacement. Alone, it's probably not enough to bend your torque rods, but it has now reduced the overall F.O.S. of the link.
(Notice how the track rod pulls the axle towards the driver's side of the vehicle when you lift the suspension height. Keep that in mind for later)
Combine this now with the forces brought onto the torque rods by axle articulation (youtube videos of solid axle articulation if you're unfamiliar with the term/concept), and you'll have a situation where the rear (AKA side connected to the axle) of the lower torque rod is pushed severely towards the driver's side of the vehicle whenever the driver's rear wheel is lifted and the passenger rear wheel is lowered (clockwise axle articulation).
The amount that the rear end of the lower torque it is displaced is equal to [track rod induced displacement] + [articulation induced displacement]
...Or:
[L*(cos(theta1)-cos(theta2))]+[d1*(1-cos(phi))+d2(sin(phi))]
where phi is the angle the axle makes with the parallel, and d1 and d2 are geometric locators for the lower torque rod.
hopefully this diagram helps visualize how the torque rod gets displaced and can eventually fail due to rubber bushings not letting it articulate enough
based on the photos of the failure, I'll bet you were turning left and maybe hit a bump with your driver's side rear wheel.
I'd also bet that you could get away with not reinforcing the subframe if you converted your torque rod bushings to heims and optimized your track rod length.