In STL last week I was told that as long as the airline you work for, operates in STL, regardless of concourse. You don't need a pre-certified boarding pass.
But it seems at AA, especially on the agent side, that the sabre entries regarding CASS, and the meal listing (AA term, the boxes cost 6$) entries change daily. I'm not sure why it is so difficult? Having used them exclusively for the past year, I have always made it to work, but a handful of times they couldn't get me verified in CASS? Luckly there were seats in the back.
I just not that difficult? D6U, D6L yadda, yadda, yadda...............