The Eulau massacre is probably the best investigated crime of the Neolithic, involving - in addition to archeologists, aDNA and isotope analysts - also modern pathologists and crime scene investigators. Last I heard, they had traced back the weapons used for the killing - they in size and shape correspond to typical Schönfelder Group axes. The Schönfelder Group settled on the Upper Middle Elbe, between a bit north of Magdeburg, and Hamburg. They had little CWC influence, if at all, but instead set forth Bernburg (FB) and GAC traditions, producing a/o a kind of proto-BB ceramics.
As concerns Sati, note
a) those Eulau burials all suffered violent death, usuallly slaughtered from behind;
b) the buried were either women, infants/ juveniles, or seniors, with regular adult males missing (the idea is that they were out for taking cattle to pasture, or for hunting, upon their return found their village folk murdered, and set up the burial);
c) CWC was a burying culture, while the Schönfelder Group used cremation.
So, essentially, there is nothing in Eulau even remotely reminiscent of Sati.
Eulau also demonstrates that "Steppic", Yamnaya-like immigrants didn't arrive as militarily superior destroyers of "Old Europe". Instead, they were immigrants suffering violence from the established populace (a quite unfortunate tradition that has survived to date in East Germany).
It finally serves as a cautionary warning: Eulau has supplied around a third of all CWC aDNA we have so far. The context is extraordinary, which should be kept in mind when interpreting the aDNA results.
However, I guess somebody excavating west of the Missisippi in some 4500 years from now may, in addition to burnt-down settler farmsteads, also recover mass-graves of violently killed Amerindians. So far, there isn't any evidence from East Germany of LN violence against the "natives". And, unlike the Amerindian scenario, "native" cultures such as Bernburg, GAC, Schönfelder Group or Elbe-Havel culture (Potsdam/ Berlin area) continued next to, and unaffected by, CWC, for many centuries until ultimately giving way to BB and Unetice. The only culture that so far has been archeologically evidenced to have suffered external violence is CWC.