Well...the Scarab already had it's own name. Sort of. Dan Garrett did use that turn with the Scarab to transform originally. Which given the Scarab's nature always just made me assume that WAS it's name and it couldn't activate otherwise when weakened until recharged in Day of Vengeance.

And that seemed to be the case/clarified when the other Reach infiltrators showed up at the tail end of Jaime's book with name's like Dho Zha.