Me and my friend tried studying this kinda thing with Cerberus, we believe with the 12 spawn spots that they spawn within a specific order... it doesn't nessesarely have to be in order from 1 - 12, but it could go in an order like 6, 2, 9, 6, 5, 9, 10, 1, 2 etc. as most of us know some spawn spots have a higher chance then others.
But studying this type of thing was too time consuming to do, I believe that guy you're talking about has some sort of hack that tells him where the unique last spawned, but meh... There's still alot of secrets in the SRO world no one knows about
