Why don't you contact Silversands and ask if they will accept a deed back from you and to send you the transfer papers if they will? Heck, you could even offer to pay the transfer fee, which is usually pretty low in South Africa. With a deeded resort in the US the term would be "deed in lieu of foreclosure." I think it would be unfair to other owners and the resort to just sit back and not pay the levy. That only increases the costs for others. The resort will have to follow some kind of rules in taking it back and then re-sell the week, all of which could take years, during which time they don't have the levy income.
Am sure others will have other ideas of how you might unload your responsibility without burdening others, such as a donation.