Actually, at this point there is nothing to negotiate. The seller has agreed to a full refund including shipping (unheard of) provided the goods are sent back and the buyer is still not cooperating. The Geeks thread was closed when it was acknowledged that all that could be done by the dealer at this point had been done.
All dealers and members should be informed how the the buyer has acted. I suspect it will be a long time before the buyer is buying (or selling)anything from dealer or member. Ken has moved on with a new paypal account. Not the first time. And certainly not the last. Goes with the dealer territory.