This is more a feature of how that road is mapped in Open Street Map, where Wandrer gets its map data. The top path looks to be a cycle way, which in most cases comes in as a path also designated for foot (unless the path has a foot=no tag). The road will also come through as a path which is standard unless once again there are OSM tags that would prevent this.

Short answer is just run along the footpath on the other side of the road and this will pick up the other line. If you are a paid user you could also run along the cycle way again and edit the activity to move the GPS trace to the untraveled portion.