So are the numen just the shamans?

Marika is said to be from the Numen people based of the Numen's rune description:

The Numen are said to have come from outside the Lands Between, and are in fact of the same stock as Queen Marika herself.

But in the dlc she is revealled to be from the shaman village. If the land of shadow was originally part of the lands between, a otherwise pretty obvious piece of information (surpressing pillar being the clearest evidence) then Marika and the other shaman are definitely not from outside the lands between. This sugests that the Numen are a different group to the shamans. I don't see how this adds up.

The black knife assasins were all Numen. The black knife armour description:

The assassins that carried out the deeds of the Night of the Black Knives were all women,
and rumored to be Numen who had close ties with Marika herself.

but are also called 'scions of the eternal city' by Rogier. Once more the Eternal cities are not outside the lands between, and so that can't be where the numen come from either.

I'm inclined to just consider this a plot hole, but can anyone explain to me their own idea?