Cisco had an option like ip flow-capture mac-addresses to export ( Enables the software to capture the values of the source and destination MAC addresses from the traffic in a flow). Will this export the MACinfo to Orion NTA?
I am not familiar with the MAC address export using NetFlow but hopefully someone may come along here with some advice on that. In case you do not find a solution using NetFlow you could use packet capture integrated with your Orion deployment.
Check out the demo at the link below which shows a LANGuardian system integrated with Orion. It captures MAC and IP addresses from network traffic and stores this in a database so that you have an historic audit trail.
Hope this helps,