Unfortunately, the warranty issue applies to most of the sales over eBay. 3DR is not unique in this regard, and eBay sellers take advantage of this by stating "Manufacture Warranty" or something similar which is simply them stating that they, the seller, aren't going to warranty the item.
I know that it's frustrating. Imagine how much more frustrating it would be if you were one of the original purchasers who had to pay $1400 plus the cost of their GoPro!
3DR and the Solo certainly have their faults, but that is why the we have the low prices that we have today. I new before I bought my Solo for a great price that I was taking a risk, but it was going to be a bargain if I could make it work. With help from this forum it has worked.
Review the eBay listing from the time that you made your purchase. If the eBay seller did make you believe that the Solo would be covered under warranty, then open a claim with eBay regarding this issue.
Know that many of us are able to keep our Solos flying with parts and help from this community. You can have a working Solo, minus the broken GoPro, with help from this community, effort on your part (it's a hobby), and the cheap parts that are available.
If you truly are giving up on your Solo, use eBay or the classified section of this forum to sell your broken Solo package. No matter how badly damaged the Solo is, there is still value in the parts and broken camera.