After much headache due to the lack of a native function on listing Site information on devices, I have found a relatively simple workaround.
Create Smart Groups with no criteria assigned to each site.
ex. 'Location 1' Site, 'Location 2' Site, etcCreate New Policy\\Configuration Profile with default config (that does absolutely nothing)
Scope this Policy\\Profile to All Computers\\All Users.
Add each of the Smart Groups for all designated Sites to the Exceptions.Look at "Logs" for this Policy. It will contain all systems that are not assigned to any of the 'Sites.'
It may not be as simple as a report, but it gets the job done.
