Won't Move even in gear

Assuming you have released the emergency brake, when you put the engine in gear (Allison shift pad goes from N to 6) if the rear brake shoes are rusted to the drum (CAN happen) you would see the engine RPM increase (torque converter slipping), but would not move.

Try putting it in D and then R. If still will not move, you will to free the brake shoes. Sometimes giving the brake drums a sharp, light rap will free them.