Actually, it was the other way around, the Morrowind Uderfrykte was the child of the Oblivion one. I think there was a discussion on this a long time ago (some of it here: http://www.gamesas.com/index.php?/topic/1161070-the-underfykte/page__p__17041132__hl__uderfrykte__fromsearch__1#entry17041132)
And the general conclusion was that the Uderfrykte was probably a Beowulf reference from the beginning, starting with the original, and then the mother, and then Dragons, so no more Uderfrykte. I don't really know Beowulf though, and i didn't play Morrowind, so no comment on it from me first-hand...
Imo, I would prefer them to get some more unique creatures, but wouldn't say no to the Uderfrykte return