On the trailer toad, the axle on it steers, so there shouldn't be any horizontal load or scrubbing while turning. As far as backing goes, you're supposed to slide in a set of pins that locks the steering out, so you can back it conventionally.
Truthfully, a device like the trailer toad is what is needed if you're hauling trailers with your bus. It eliminates the magnification effect that you get by having the tow point so far behind the rear axle.
You can try the air ride hitch, but you're still going to get the large up and down swings every time either the front or rear axle crosses an obstacle, it will just be cushioned slightly.