For this purpose and many more, I used Netwok Performance Monitor by SolarWinds.
Microsoft Network monitror 3.4, a free tool is also best tool to find all the noded connected to any subnet and the ports which are being used by them.Its free and available on MS websit.
Nothing in ePO per say. If they have implemented it, I haven't found it but there were discussion to be able to track the rogue device to the sensors to al least get a site.
Anyway, my understand is you can go on the switches and find the with interface (port) the mac is showing up on...
On cisco it would be similar to this:
show mac address-table
Out of curiosity, how would you find the swicth port a mac address is coming from using NM3.4 ?