I don’t think Yoda was added until much much later.
I’m certain that’s true. I’ve always felt he looks “off” in that image. I mean. he looks good. Looks like Yoda. But the style seems inconsistent with the rest of the artwork. The other additions blend more naturally.
Maybe it’s because Yoda is in a recognizable pose from the film. The rest seem to be painted from BTS stills and such, but Yoda is definitely from the film itself.