So now I realize that they basically told us how this was gonna go down in the “previously on Grimm” part of this ep.

Schrodinger’s reality.

Until Nick made his choice, both realities technically existed. Only when Nick made the choice to stand up to Zerstorer and fight him did the reality in which Zerstorer loses solidify and become The reality.

Which means if Nick had chosen to give in…he would have been trapped forever in that horrific reality where everyone he loved was dead.