These actually do have faction, you just don't get any faction hits for killing them. The only reason they're on a faction is to determine how they react to you. I'm not sure which faction they're on, but killing TM coteries lowers your faction with the undead in katta.
Yep, it is now. It wasn't at the time I posted the information and sent in the correction. The updating for this mob to Undead in the bestiary was really quick. The correction showed here at the site about a day after I sent it in.
The information in older posts is based on what was the state of the game or the state of the database at the time. Often, because of some in-game change, or a correction to the database, the information in an older post may appear to be wrong, when it really isn't wrong so much as just no longer current.
For what that it matters, this mob should be classified as "Undead" rather than as "Monster." Combat spells designed to fight undead work quite well against this mob (and, of course, all the other undead mobs in the Katta graveyard.)
Also, this mob, and all other undead mobs in the Katta graveyard have no faction. Killing these mobs do not raise or lower any factions whatsoever.