Well, I don't get the path cost returned(Feature request, right there.), so it's hard to look at that. However, the only difference in the path that's 98 and 97, is that at some point along the way it moves in direction 8, instead of moving 1 and then 7, all of it is on road, but since moving 1 step diagonally is both faster(tick wise) and costs the same as moving up and then left, the difference in cost would be 1.
