In my "Creatures without clan," the Sandisia Daggers event pets do not show up in the dropdown "Series" menu. It's like they don't exist.
Searching for Quest or Holy Paladin pets in the "Type" menu doesn't bring them up, either.
EDIT, when I select "Species," "Position" (one of the positions of a pet from this series, for example, "Destrinos 1"), "Year," AND "Type," the Sandisia Daggers pets come up in search results (at least, one of them did when I tried this), though the series name still doesn't display in the "Series" menu, it just says "All."
EDIT, selecting "Species," "Year," and "Type" also brings them up. So all that seems to be missing is their Series name.