If the buyer uses eBay's money back guarantee you will have to accept the return. eBay never sees the itm concerned and in cases of uncertainty generally finds in the buyer's favour.
It certainly does look lke a very dark jacket. Part of the difficulty is that because there's almost no background showing in the photos. This makes it harder to tell exactly what shade it is, because there's nothing to compare it with. Even the camera can be fooled if almost he whole image is the same shade.
,