Extreme Networks

Looking to do an API query to the Site Engine End-System "MAC OUI Vendor" column and for the life of me can't seem to find it.  Anyone know the field to API query?    

Trying to get to XIQ -> Control -> End-Systems (Last Seen) using the GraphQL.  Just cannot find it.   Here's the GUI, but I want to call it in XIQ to get the "MACs" and the "Last Seen" dates.I've tried the below, but doesn't seem to be the right fiel...