Your question is Handling a Disorganized Interview Loop. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You are in the middle of an interview process, and the experience becomes disorganized. Schedules are unclear, handoffs between interviewers are weak, or a key interviewer does not show up. You still want to represent yourself well, get the information you need, and avoid creating unnecessary friction.
How would you handle a situation where the interview process is disorganized or a key interviewer does not show up?