I thought the AmeriQue is a true set-it-and-forget-it smoker/cooker. The brisket might have been done at 8 am had you not had it turned down to 200* for 6+ hours. Without sounding too smart, (probably too late) I think you should use the smoker as it is intended, set-it-and-forget-it. You turned it back up to 225* at 5 am. It might have been to 190* by 10 am had it been on 225* all night. Make sense?
Disclaimer: I do not have an AmeriQue, nor do I have any idea what it is like to cook in one.
Main thang: brisket is good enough for chili or beans.