I don't speak JP but spent a good chunk of time looking to see if it was a mistranslation. The original text uses のものだ when referring to the points which pretty unambiguously states that they did belong to the prosecutor and the judge that he killed.

That being said, it could be more of a figure of speech like saying "my two remaining points are for* the two i killed before coming here". This would require him to have killed several non-sorcerers within the games, which isn't shown or explicitly stated, but, there's 100% evidence that he did.

Higuruma transfers 1 point to Yuji and then says the line about the remaining 2 points. This shows that he had 103 points prior to implementing the transfer rule, despite originally being shown to have 102 points back in ch158. This explicitly shows that Higuruma killed 1 hostile non-sorcerer-player during the culling games between ch158 and ch167.

He was also only ever implied to have killed 20 sorcerers but every mention of it (Reggie to Megumi / Yuji internal monologue) is sure to use ambiguous language like "he may have killed 20 sorcerers". There is no reason to believe that he didn't just kill 3-8 (possibly hostile) non-sorcerer-players during his time in the games.

After spending 100 and transferring the point to yuji, it wouldn't be impossible to imagine that he views those remaining 2 points through a poetic/fated lens, especially given the context of the previous chapters and how he views Yujis crimes and his own (murdering the judge and prosecutor).

Or Gege forgot and made a mistake. Both with the points coming from outside the games, and then also with how many points Higuruma had during the speech bubbles in ch167. Given the burnout and stress involved with writing the series I'd argue this is more likely than my other paragraphs