Blackboard vs. Isolated Workers for a Multi-Service Incident Investigation

During a production incident, you want to spin up one agent per affected service (5 services) to independently investigate logs and metrics, looking for the root cause. A colleague proposes giving all five agents read/write access to a shared "incident scratchpad" document so they can see what each other has found in real time, arguing it will help them converge on the root cause faster.

1. What does the shared scratchpad buy you here that fully isolated workers reporting back to a supervisor would not?
2. What does it cost, concretely?
3. Propose a design, and justify whether it uses a scratchpad, fully isolated workers, or something else.