John Goode or Don Lombardi, the two founders of DW Drums, may be able to provide the answer. These guys started out in the drum business by manufacturing trap case seats for the Camco Drum Co. They later purchased the machinery, dies and molds, and everything else it took to make Camco drums and hardware (they did not purchase the name).
The non-round lugs appear to be a Camco "Tuxedo" outfit. I never knew that Camco had two styles of lugs.
Center lugs were the "more affordable" drums, put out by most major US drum companies. They used the same shells (usually), but used budget hardware. And where the 22" top line kick drum would probably be a 10 lugger, the budget line most probably would have 8 lugs. While the drums would share the same shells, less holes drilled (less man hours) and budget hardware, would make the drums less costly.
makes sence