The Peer is the MAC address of the Auto VPN Peer.
Searching by Inventory makes it easy to identify the Peer.
I think the reason it is not the name of the device is to uniquely identify it when the name is changed.
There may be a problem between the MX of the Network that is outputting that log and the Auto VPN Peer.
Meraki MX's Auto VPN Tunnel Failure Detection is at 5 second intervals.
Therefore, It is possible that the ISP did not detect the problem due to a short period of flapping.
Incidentally I contacted support, but the detection interval cannot be changed.
For your information.
In my work environment, Meraki MX & vMX are flapping to the point of concern.
I think it is because we are using Internet connection and cannot control the quality.
Personally, I would like to know if it is the same in other production environments.