More like those equivalents, if I had to guess.
I also have to add, though, I think Niflheim was more Ginevra's addition, rather than Ariana's or Kim's.
(Ginny's thought up books Aidan Flamberge might read, in her free time in 2017 and 2018.)
Ginerva, eh? So I take it she's taken inspiration from T.E.D in order to think up those books?