IAG,
If you want to make the principle/term "sabaki" that general then yes Willie Oliver was doing sabaki.
Incidently I never said that Ashihara or even Ninomiya "created" sabaki. Sabaki is probably as old as the martial arts itself. Sure I am sure people were using some type of Sabaki.
But we're (at least I am) talking specific here. To imply what Willie Oliver was doing in some way was the same as what Ashihara and Ninomiya did is to over-generalize the matter in my opinion.
Willie was just trying to be "cute". He was doing his version of the Ali dance/shuffle along with what I call the Bruce Lee goodstep. It looked good but that's about it.
Sabaki is more than just evading punches, kicks etc. It is more than just "body movements in order to avoid a attack."
First off Sabaki can be both offensive and defensive so it is more than just "evading". Secondly the "purpose" of Sabaki is to put yourself in a position of advantage.
Here is an offensive example of Sabaki I use in Judo:
The opponent and I have left handed grips on each other (our left legs are forward; our left hands are grabbing each other's left collar; our right hands are grabbing the sleeve of each other's left arm).
I want to apply a harai tsurikomi ashi on the opponent's left leg. But in order to do this his left leg needs to be back, in the position we are currently in his left leg is forward.
I pull my opponent to his right using the combined effort of my left arm, hip and leg. This forces the opponent to bring his right leg forward, which means his left leg is back. This is what I want.
I then step around his right leg and attack his left leg with a harai tsurikomi ashi. The opponent is thrown.
This is just one example of "sabaki" used offensively.
What Ashihara and Ninomiya did in terms of using Sabaki was both offensive and defensive which, I dare say, alot of people in Karate were not doing.