Microservices – saga choreography

I am usure how to maintain consistency in a microservices architecture system using choreography for transaction management.

Take this simple architecture :

For the Operation #1 and #2 I can use the Outbox pattern to ensure the changes in the database result in a message being published on the Queue.
Or simply One Phase commit where I nest the database transaction inside the boundaries of the Messaging transaction :

• Start messaging transaction
• Start database transaction
• Receive message
• Update database
• Commit database transaction
• Commit messaging transaction

But what about the operation #3, #4 and #5 where I have to :

• read the message
• write to the database
• send a response message to another queue

What can I do to make sure that, after I committed the DB transaction, I also post a message in the response queue ? I want to avoid the possibility that the DB transaction in PaymentsDB is successful but no message is sent on the response queue.

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