This thread is a bit of a hot mess, that's for sure. I've mostly stopped paying attention to it. I figure if anything has anything worthwhile to contribute, it'll be submitted and I'll deal with it at that point.
These NEXEDGE systems can grow quite large (see the Mobiletech system for an example), and so there's really no reason for them to use two system IDs for a single system, especially where they're duplicating the site IDs.
Oddly though, it's not like the 448 stuff is in a group. Warning: speculation in screenshot