It's an appeal REQUEST. "The determination dated mm/dd/yy is wrong. I want an appeal hearing scheduled," is sufficient. You save your words for the hearing.
I disagree that it was a refusal to do your job. You didn't want the pulling of the weed roots to mess up the fabric.
In CA, a lot of the hearings are in person, and there's a great shot that your employer wont' show to tell this story about how you refused to do what was asked of you. With you not there, he's probably going to be very busy doing his own job, and yours.

