Wow, the dress looks great on you! If I wore one of the zip-front dresses I'd look like a ten-year old playing dress-up, but yours looks incredible!
Honestly, even though it's a product with an undisclosed defect, I personally wouldn't feel comfortable asking for a refund from money that's going to charity. If you are sure it will come from the seller or ebay, then perhaps, but I think in situations like this, it seems more likely to be subtracted from the charity's total. I could be wrong - I don't know much about ebay - but that would be my initial reaction.
So, if I were in your position, I'd take the dress to the best dry cleaner you can find and pray for the best! Or, if you'd prefer to go down the partial refund route, perhaps first of all check with the dry cleaners whether it will be removable, get a quote, and just ask to be refunded the cost of the clean. Good luck!
yeah, i am thinking that at the end of the day i can just write the money off as going to charity, since i would be fine with donating the money directly to charity without the dress. i am mainly concerned with how to clean it...i'm thinking of taking it to a dry cleaner to see what they can do -- anyone got a rec for a good cleaner in the bay area that won't ruin herve dresses? melody i'm looking at you, haha