Well, the AoL AA mentions Sel, so that means that the AA writer is definitely a worldhopper.
In my opinion, the AA writer doesn't avoid discussing Adonalsium because he/she doesn't know about it, he/she doesn't mention Adonalsium because it isn't specifically relevant to the magic system that's being discussed. The author is presumably writing the AA for himself, or other worldhoppers, and the target audience already understands Adonalsium, so there wouldn't be any need to explain it in the AAs.