If you disconnect leads to motor than momentarily apply 12v to the leads of the motor would move slide in or out.
Once you know what direction its going reverse the leads pos & neg, motor should move in opposite direction, will prove if its the motor or gears binding.
If you release the torque nut you will free up drive shaft and can turn shaft with wrench to move bench slide or long living room slide into coach.
It should prove the motor is defective, motor may heat up if can not move other direction or if you are monitoring motor leads may also see a different voltage lower than the 12v's.
Check this thread.