am assuming there is a switch near plug wire from trailer, that by passes the regular brake wire / control on vehicle, to cause brakes on trailer to lock up solid temporarily while getting wheels back to center position on trailer. assume instead of generic 4pin, using a 7pin trailer connector, and using the aux 12v on plug, to by pass over to the breaks. perhaps with a DPDT switch?
first looking at trailer, was waiting to see some sort of hand crank with wires to pull wheels back and forth under the trailer. and then was hoping to see some sort of hydraulic cylinder that moved wheels back and forth. hyd cylinder something like you might find on a regular dump truck / bed that lifts up and down.