Good to hear from you again, I've been through the same stuff, been through a modelling dry spell. Since I've kinda ran out of interesting stuff and have completely remade everything that needs remade so far.
They were indeed different, the Landstalker seen in-game had 4 legs, the 8 legged one was apparently cut from the game. Also, I'm also considering making the Chimeran Stalker, from Resistance: Fall of Man (another Insomniac title, and apparently it used the Landstalker as based code.).