An incomplete list but hitting the big ones: Superbike swingarms, motors, electronics, and frame strengthening would not be allowed. Without those it is definitely not a Superbike.
They are riding Panigale S bikes. That gets them around the rules since they are a different capacity spec.
Do we know which other of the BMWs got the new swingarm? I've read VDM had it, but nothing on the rest.
We ran into the Hayden boys (and a few other AMA Pros) who were having some fun at Grange (Victorville) We were doing our cheaters practice the week before a SKUSA event.