To be honest, I can't see that negative feedback is justified there:
1. Is it genuine? Yes, it would seem so.
2. Is what you received the coin pictured on the listing? Yes it is, so no issue there.
3. Is his description misleading or wrong? Not really - he did not assign a formal grade. "Very High Grade" is entirely subjective and not far out. Very Fine also contains the "very" word. I would give a solid GVF to the reverse but only VF to the obverse - which is typical with Victorian silver. His pictures look OK to me - I can't see he was hiding anything there.
4. Was the price fair? Probably a bit high, but you chose to pay it.
Negative feedback is a big deal for regular sellers, so I would save it for a really bad listing. If you are really unhappy with it, ask to return it for a refund, don't hit him with a negative out of the blue.