I am gonna offer an opinion. Unless a custom order, which is unlikely, it wouldn't be out of the question that that bottom knife was "tipped" and "repaired" at the shop. I believe ti started life as a model 4. Note the center bevel line is not in line with the tip as on the model 4's. I don't think RMK was making anything resembling a Green River Skinner prior to the Bowles knives that I have seen, until now