OK, I have thoughts.
For background: I struggle with nightmares, am afraid of my own bed, usually sleep on the couch with the TV on, and I smoke weed at night to dull dream activity.
My abuse was between 4 and 7 years old, and like you I froze during it (as best I can remember). Freezing is a 3rd response to trauma along with fight and flight, but freeze isn't usually mentioned.
A few years ago, researchers discovered the chemicals produced by the brain that induces paralysis in the body when a person goes into REM sleep, so that a person doesn't act out his dreams. Here's a link:
https://www.livescience.com/21653-brain-chemicals-sleep-paralysis.html
Now -- my theory is that the nightmares come from the brain paralyzing the body to prepare the body for dreaming, and another part of the brain that associates paralysis with trauma concocts dream narratives that are repeat trauma loops, because the brain associates paralysis with trauma.
If I'm reading your dream correctly, iaccus, the terror comes from "can't move," "no escape," surrounded by killers, unable to fight back... right? It's the same thing that happens to me.
I don't have a solution for you other than to smoke weed and sleep on the couch with the TV on so you don't hit REM sleep, but that's not much help. Just know that I think there's a biological reason that it's happening, although I don't have any answers about how to make it stop.
Cant