You've killed us both

[Kein]

That's a bit of a stretch, since not only does the ending imply the opposite, but in all endings The Shadow comes in force, and does not waste time. So for it to curiously ignore the victim it's been chasing at length is seemingly a contradiction. "Hey Alexander, surprise, you die now! Yo Daniel, I'mma let you finish, BBL kthx bye. - The Shadow"

For a man who escaped teh Shadow som much times (and with our help as well) - escaping it another time is a piece of cake. I'm not even surprised.

Regarding to other endings: Shadow was chasing Alexander as well, but since the Inner Room as impenetrable coz of Orb, Guardian decided to took Daniel first. Now, if you remember, we broke that protective barrier and Alexander want to escape from Shadow in to other world which implies teh fact: Guardian can't follow him.
Back to the endings: the first one, when you let Alexander escape, the only victim is you. The second one, when you help Agrippa, it happens that you move with him to the other world, because, as you remember, there was Weyer as well (who is supposed to be on the "other side"). Such conditions clearly states that Daniel escaped from the Shadow.