So i guess this chapter rules out that Shanks and Gaban knew even what Harald's proposition was to Loki, at least immediately or the point where Loki probably needs to escape Elbaf for being a scapegoat. Jarul heard it but got stabbed in the head and probably doesn't recover until later, explaining to them what happened. Hadjrudeen never finds out which suggests Shanks or Gaban actually never find out about it.
Idk how Loki gets captured (if Shanks directly defeated him or not), but given Gaban's dialogue warning Luffy about him it doesnt sound like everyone knew the full story.