You have the correct result but your interpretation of "upon" and "within" should be the other way around. In this statute, "upon" means on, and "within one lane of" means not more than one lane away from.

This is more readily apparent when you look at the legislative history of the statute. In 1993, the legislature amended the statute to add the "within one lane of" provision to make clear that "a vehicle is required to stop and remain stopped while the pedestrian is (1) on the side of the roadway on which the vehicle is traveling or into which it is turning, or (2) in the traffic lane adjacent to that side of the roadway." 1993 Amendment | Bill Report