How a process manager tracks communication between aggregates

Question

Does the process manager use correlation identifiers or aggregated data to track the process that it controls?

To make this clearer, consider Figure 2 on the Saga on the Sagas :

First of all, is the process manager sending the event OrderConfirmedwrong? I (as a process manager) cannot send events, but only issue commands. Or am I wrong?

Secondly, how does the process manager correlate OrderCreated, SeatsReserved, PaymentReceived events from different aggregates? Is this a correlation identifier that each aggregate honors (and copies), or are these specific identifiers (for example, SeatsReserved has an order identifier that refers to a set of orders)?

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Answer 1

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Answer 2

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Answer 3

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Answer 4

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