Ah, not magic, but an unbound soul then, infused with arcane and void (they would need to consume fel to align with chaos, i know of none like that).
Still, it seems hard to mistake their form of immortality with Alleria's, likewise their ignoring rules of reality is hard to mistake for Alleria's.
I mean for the sake of an argument you might want to pretend they're equal, but it does not seem worthwhile to take that claim seriously given these extremely obvious disqualifications - per your own source. And while the claim regarding Alleria still seems spurious, Locus-Walker being infused with void and mastering it is irrelevant.