I agree that they knew. They admit that they knew. AB getting a lawyer and BR requesting an in-chambers meeting might have been a CYA move because due process was already in question, imo.
I would guess they went into that day assuming a DQ hearing date would be set, not more violation of due process. Since they had been ordered to stop working the case, and no record was made as to what would be heard, then nothing should have been covered other than a DQ hearing date. That's just my non-lawyer thought.
It's kind of like going in to take an SAT practice test, but told not to study for it, and then when you get there, you're told it's the real test and you can't take it again.