You cant unring a bell that has already been rung.
Dont open up a can of worms unless you intend to use them all.
They have to show that you failed to follow instructions, which I am assuming was the "did not know the next three stops, or where they are on the truck." Might be that you need to try and focus a bit more. Also, that was not a condition of your initial employment(to know the next three stops), as you did make it as a driver.
As for people that have this type of problem, when someone gets all over them, or they have the impression someone is watching them to judge performance, the performance generally degrades to become even worse. And the more attention that is placed on the issue, the worse it becomes.
I would be careful about the timing when you do decide to ring that bell. Because once rung, things will change, and maybe not in the way you want them to change. Example, you are now a driver. Ringing the bell most likely will cause you not to be a driver any longer, but move inside instead.
So think long term.
As for ADA issues, a lot of people are self proclaimed experts that think they know the answer. I would suggest spending 75-150 bucks to actually get a legal answer.
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