have you confirmed the connection and wire from the trans motion sensor (down low under the trans. I think on the right side as the operator sits)?
Do you loose the fuel pressure? That is about the correct pressure for this injector setup fuel rail, but the pressure should remain constant.
On this truck, the trans solenoids are powered through the ECU, and this truck even has a signal to the ecu from the directional control for neutral, not like most older units where neutral was just 'no signal'.
A failure of the ECU to see any signal, or a signal on neutral as well as a direction would produce a p22 error.
I would strongly suspect the oil sender, which if you had the software and cable, you could hook up and see a 'low oil pressure' error signal, that will reset just like it resets when the motor starts up (and if that low oil signal shut _off_ the motor, how would you ever get the motor to start until it had oil pressure pumped up?).
I find it does not matter {much} what language the operator speaks, _I_ am the one that has to be able to talk "forklift" to the machine.

old joke time; do you know the difference between a "professional" mechanic, and a "shade tree" mechanic?
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wait for it
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the 'professional' knows how to talk to the machine, the 'shade tree' mechanic only knows how to cuss at the machine.
;-)