I never noticed those were two different sabers. Oh well, the issue stands, there is nothing special about the saber.
Of course I can imagine him just picking up the saber somewhere, but wouldn't it be a little random? And him picking it up somewhere on Coruscant is in my view no different then picking it up on the lava bank.
Anyway, Bob did a good job and it's an inspired idea, but I just don't really think it works. Still looking forward to the edit though!