If you search this forum you will find a post by Lorne Peterson talking about the various different versions of Walrus mans demise…
Basically Lorne Peterson declares the head decapiticion was never intended to be used, which I can buy into as the sound mix with the squeling suggests the arm was chosen and no variation to that, but then we must hear a lightsaber strike when Luke looks and watches whatever limb or body part get’s lopped off which is in the video I posted.
But they were unhappy with the original flipper arm shot so they were asked to reshoot the arm… all they had to hand was wolfman hands and not the flipper hand of walrus man so that is why it is the way it is in the film.
There is no such story for Greedo and Han’s scene in the cantina no squibs in the wall, no sort of oh that might of went this way or that way no crew members rushing forward to spill the beans on how Greedo shot first and missed because it’s not something that was ever planned or even earmarked for change. Thats all really. Even if they decided to swap scottish Jabba for Greedo at docking bay 94 to collect Han’s debts the fact they did the pick ups in cantina is basically case closed that it was cited as 'needs to change" and identified as such.