>> the fork keep jumping the friction wheel hub and stays in reverse...
If the fork jumps off the bearing arms the friction disk should stay where it is. If to the left of center of the drive then it will go in reverse. If to the right, forward. What direction it will go when the fork is off is a crap shoot.
The washers are not special. They help keep the fork in position. They stop the fork from going too far up and down on the bearing arms. If they go too far they fall off the bearing arms.
Since you forced it so much you may have bent something also.