I have never seen a Chewbacca with an inverted V footer, however you didn't specify which cardback he was on. I suppose it's possible there may have been a few with V footers, perhaps on non-Kenner or non-Palitoy cardbacks, but I think it's more likely that it's a fake. However, I have also yet to see a really good fake cardback that ticks all the boxes you should be looking out for. That's not to say that someone somewhere hasn't produced a perfect cardback with perfect printing, perfect blister, perfect footer, perfect punch and perfectly sealed it with an indistinguishable waffle pattern from a real one, but I doubt that's what we're dealing with here. If the Chewie is a fake, and if the forger didn't know which footer to put with it, I doubt the rest of the card is up to scratch either.
However, photos would be a good place to start so that I, and the doubtless many others much more expert than me, can offer our help and opinions, if you want them.