Exid is correct, that's not what is happening here. If Alfiya's ability was worded, "light attacks gain....." then the source of the 2 damage would be the attacks themselves, but that is not what is happening here.
Let me clear up her ability real quick for everyone.
For reference, "When an enemy creature recieves a Daze or Stun condition marker from a light attack, they also recieve 2 direct light damage."
@Beldin Your list is wrong in a few places.....
#1 Zone has nothing to do with it. As per the Banish FAQ, banished creatures are still in play. So if you banish her, the ability is still active. A cleric could even use their turn to pray, although the banish prevents her action marker from changing; it is still a legal action.
#3 Attack bar is irrelevant. Hypothetically a Satyr Gruff like ability that did either condition instead of stagger would still trigger the extra damage. Effects box and attack bar are irrelevant.
#5 If your reverse attack an enemy paladin's luminous blast and they give themselves a daze, they would also recieve the extra damage, source is irrelevant.
The only thing that matters for her ability to trigger is that an enemy creature, releative to Alfiya, recieves a light attack that results in a daze or stun. The additional 2 direct damage is applied to that creature from a global effect, like idol of pestilence, and as such does not have a source.
So in a game of domination, if that luminous blast dazes a orb guardian, it will still receive the 2 extra light damage as all of the qualifications have been meet: it is an opponent that received one of the conditions from a light attack, make sense?
Also keep in mind that light pulls double duty in the system, it is a damage type AS WELL AS a subtype that appears on many cards. Either of them is enough to trigger the extra ability, although I don't think there is currently a card that deals a daze or stun and is a light subtype and not light damage type, but I figured I would mention it here for illustration purposes, and you never know what the future holds.