Elite Skills from EOTN

Ive been browsing in Guildwiki, it seems every elite skill capture in eotn can be captured from any other campain of guild wars, arents their elite skills that can be ONLY captured in EOTN Campain?

Only if you count the Norn Blessings.
GWEN is only an expansion, and introduced no new Elites.

It is also my understanding that you must have the campaign where the elite skill originated from in order to cap it.

You can cap it, it'll just have a lock symbol over it and not let you use it. Although, all the elites in EotN might be core, but I dunno about that.

Nope, I'm pretty sure Presevation isn't a core Elite, Rit's aren't a core class. However I do believe there are a couple of core skills up there.

They changed it when EotN was released. You MUST have the relevant campaign to capture it now.