Salat defined as "duty" at 3:38 does make sense. Zakariah is asking for guidance (in the sanctuary), which is his duty. The duty is to serve and ask for help from God alone as declared in the first chaper and the first line of the second chapter, did you even read the article?
And salat cannot be equal to "prayer" singularly since, according to the Qur'an, Allah must do his Salaw to mankind on the day of Judgement, which is why the revision exists in the first place. Your religion as it is is a beehive of holes. You know this. Peace.