Ah, the joys of copyright confusion and platform policies! It's frustrating when your artwork gets taken down even when it clearly doesn't mention or pass as a merchandise for the band, in this case Nirvana. Redbubble's dispute process can be a bit of a letdown since they don't provide much individual advice or opinions on these matters. It seems like they're playing it safe by erring on the side of caution.

In the world of intellectual property, things can get pretty complicated and subjective. While your artwork may be a clear parody without infringing any copyrights directly, platforms like Redbubble often prioritize avoiding any potential legal issues or complaints from rights holders. Sadly, their focus on risk mitigation sometimes means that genuinely original and parodical works suffer.

It's always good to keep pushing boundaries in art and expression, but unfortunately, some platforms might not fully understand or appreciate that nuance. So stay true to your artistic vision and keep exploring alternative avenues where you can showcase your work without unnecessary roadblocks!