Have you turned up the EO so that you can observe the flow. The proc you show has echos and so you should be able to detect the activity with the noise level up.
In any case, the engine is trying to route what appears to be an ACK so that particular message was not handled.
Please note the message type is DATA not REPLY in the metadata – that may give you a clue.
Jim Kosloskey
email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.