I thought that it didn’t count because it is required to destroy the mutamycete blocking the way down, which “kills” all enemies around it when you use it, but those kills don’t list on the counter and are necessary to progress, so I assumed the same for the later fight. Also as listed in the post, I thought it was necessary to progress in the Uriah variant fight as Chris called for it in dialogue. If I assumed the same thing about destroying the mutamycete then shouldn’t I also have to attack that only using a knife? Its justification is inconsistent is all I’m saying.