I don't think that counted as Wind Release: Rasengan, since it wasn't really a perfect compressed sphere, but a round unstable mass of wind release chakra. So you could say in this filler, Asura used a proto/pseudo/imperfect Wind Release: Rasengan.
In addition to what everyone else has said, I want to add that the Rasengan was explicitly stated to be based off of the Tailed Beast Ball, which automatically makes it structurally and functionally different from whatever Wind Release technique Asura was using in this episode. It looks like a Rasengan, but it's not.
Just like Chidori/Raikiri are similar to whatever technique 3rd Raikage used.
As our friend NeedleJizo has stated, the conception of the Rasengan came to be when Minato observed a Tailed Beast Ball. On top of that, the Rasengan was said to be the highest level of shape transformation, while Asura's Wind Rasengan-like orb clearly isn't well shaped or stable.
But sure... for all intends and purposes, Asura used a prototype 'Rasengan' but not really an actual one.
just look at it this way. Chidori looks similar its actually some what spherical. when ashura used his wind release technique it actually just looks like visible chakra it doesn't really look like rasengan it looks more like a chidori without the chi chi chi sound
We don't actually know for sure that Minato created the rasengan based on the Tailed Beast Ball, that was just Killer B's theory.
When Naruto tries to form a rasengan it automatically became a Bijudama. No more proof is needed.
It became a Bijudama because he was trying to do it with pure Tailed Beast chakra instead of his own human chakra. The structure of the two jutsus are basically the same, with the difference that the Rasengan spins, and that´s what makes it stable enough to use by humans, and that it doesn´t need the precise 8:2 chakra ratio. Naruto´s Biju Rasengan is the result of the structural similarities of both techniques, with the added difficulty of stabilizing the 8:2 ratio. My point is that they are similar, but they doesn´t need to be related. It´s like comparing the 3rd Raikage´s Hell Stab with the Chidori/Raikiri. They are similar, but they aren´t necessarily inspired by one another
^ Also, in the Rasengan section, literally the first thing it says is 四代目火影が '尾獣玉' にヒントを得て (Yondaime Hokage ga 'Bijūdama' ni hinto wo ete), basically meaning "Fourth Hokage, by getting hint from 'Tailed Beast Ball'".