In books, usually we can read for TPs that give us spells, 'Open own realm', but I think that is an errata or, in any case, non-appropiated.
IMO, a list obtained by TP is always a TP list, and its realm is not going to change for that, so if a magician learns necromancy with the necromancer TP, the list is yet from channeling.
We have a cost for 'other realm TP spell list' that is never used.
From beginning, we use that a spell list obtained from TP is a TP list, so if it is your realm or not, you use the appropiated DP cost, but always as TP list.