Dan, do you have any more pics of the brisket slices ? Also, did the slices have a little pull tug to them ? Or did they just fall apart when tugged ?
Just trying to nail things down because both undercooked and overcooked brisket can be dry. The more undercooked it is, the more tug it will have. When it's overcooked, it tends to be crumbly and falls apart. A third option is if it spent too much time in foil, it will be mush, but usually, mushy brisket is still very moist.