?
According to Sprig there were unsuccessful kill attempts on nights six and seven. JohannaK died day 8 and was Korean, Snerk died day 10 and was mafia. There was no kill attempted nights 8, 9 and 10 (unless someone hasn't spoken up about being attacked and surviving). So scum have died since the last known night kill.
Early in the game there was speculation, based on the descriptions of the kills in the narration, that there was more than two scum factions and that they do not each kill every night. We now know there are more than two scum factions.
There are also several roleblocks flying around. Verarde proves that there are redirecting abilities in play in this game, and we can't be completely certain that his was the only one.
So we have multiple roleblocks that we can't necessarially be 100% certain blocked who we think they blocked. We have multiple factions that may or may not be able to kill only on certain nights (rather than every night). At least some of which are almost certainly killed off. Hell, with how complex things are there could be a scum faction with no kill but some other goals. In short
things are complex. There is more than one explanation for the lack of kills in the night. With all that, claiming that scum is "refusing" to kill, that they are actively choosing not to kill, is...weird. How can you be confident in that conclusion?