While I can understand why some people can view this chapter as boring and Jubach's killing of his men being pointless, I think we need to look a bit deeper at what happened.
Bach's entire invasion plan can revolve around Haschwald's mysterious Balancing power. As long as he manipulates the balance to remain on the Sternritter's side, they can stay on top of the invasion. If two of the Sternritter are defeated by the Captains, but revived through their Vollstandig, then perhaps the balance is upset and Bach had to have them executed to preserve this balance that he needs.
Haschwald's power could be that he can defy reality if the balance is upset and he can manipulate events so that balance would be restored back towards his side, even if he wouldn't be able to do so normally otherwise. (Cutting the otherwise uncuttable Cheng Du.)
All theory of course. But I think there was a reason we were looking at Haschwald's balance scales during the execution.