Have we even seen Salmon getting send to the future. If not he (non cyborg Salmon) could come and attack the shades in the last moment and that sends them to an alternative world each. This would mess up Salmons memory so he think he was send by Threeshades.

By the way the ningas live in another world but come from Avbaroy. They just live in a Demi-plane filled with a good and friendly darkness.