Well, nobody can connect this version with the current version save from certain people who noticed they have the same halo.
+heterochromia + same hairclip + usage of both an AR and a pistol + hair color
Though, technically speaking, the actual identity of the character isn't confirmed. It probably is Shiroko, but it can't be confirmed because it hasn't been explicitly stated. The halo certainly looks like Shiroko's, but it's also longer at the ends of the crosshair and also pointier. The pointiness can't be attributed to the fracturing effect that's observed from a halo possessing the attribute of "terror," as has been seen with the Justina Devoutee enemies in area 12. It's possible that her halo changed shape with age or something, but there's been nothing mentioned in the game afaik that states that a halo can change shape over time.