FWIW, I think it's very honorable of you to refund your renter's money. However, to say that abiding by the terms of a contract is "reprehensible" is a bit over the top. Travel insurance exists for a reason, and renters knowingly gamble with their payment if they choose not to buy it. Without it, the only remedy for being unable to stay in their rented unit during their rented time period is to be rebooked.
Same for your resale ownership. When you chose to save money by buying resale, you knew the only alternative to having use of your unit was to deposit it into II. I understand what you're saying about this being a once-in-a-lifetime catastrophic event, and I feel badly that no good options are available to you, but I also understand the flip side. I myself often choose to travel without insurance... and I understand and accept the risk of doing so.
That's an interesting perspective - "abiding by the terms of a contract." I actually litigate contracts cases for a living and unless your contract said "you owe me the money even if I don't deliver my half of the bargain" (which itself could be of questionable validity), I don't see how an owner is abiding by the terms of his or her contract by refusing a refund when the resort is closed. Advising a renter to get travel insurance doesn't cut it -- that's intended in the event I'm ready to perform but the renter can't or doesn't want to anymore (sickness, death in family, lost job, snowstorm cancels their flight, etc., or bankruptcy of the supplier). I would bet money that the travel insurer of your renter will not pay the claim and, if they do, they'd sue you for the money back because you are the party who didn't perform by delivering the villa in livable condition. Of course, you wouldn't be in breach for not performing - it is force majeure. But it doesn't mean you are entitled to the other side's performance without yours.
The Westin is no doubt refunding all payments of people who made non-refundable reservations directly with them. You think they'd have a leg to stand on if they told you that the reservation was non-refundable, so sorry that the hotel is closed but you should have taken out insurance? Why are you any different? What would the internet outrage look like if a hotel ever tried that (putting aside bankruptcy, of course, since there's a whole legal regime and rationale of equal treatment of creditors behind that)? Or when someone buys something on the internet that's "final sale" but then the store has a fire and the item is destroyed before it is even shipped to you -- do you think you still have a legal obligation to pay for the item because you knew it was final sale and delivery was irrelevant? I don't think this is even a close call legally.
But yes, even if you had a chance of winning versus your renter, I think that it would be reprehensible to stick it to the renter. They were willing to pay me $6,000 in return for xmas week at the villa. I should profit from this tragedy and, even worse, make someone pay $6,000 for a villa that I can't give them? Why is this any more morally acceptable than raising the price of gasoline when people are fleeing a storm (after all, what's wrong with free market supply and demand?)?
The only close call, in my opinion, would be what to do if the resort had reopened by xmas but the renter no longer wanted to come because the facilities were still under repair and the island needed rebuilding. I think a good argument could be made both ways in that circumstance, both legally and morally. The proposal I was in the process of making to my renter when we heard of the cancellation was that if they didn't want to stay there under those circumstances, we should donate the rental fee to the rebuilding effort.
As far as my disappointment in Vistana, I fully understand that's my bargain. They could generate good will by giving me an option, but as I said in my original post, that's entirely up to them and they have no obligation to do so. I suspect there are not a lot of people in my shoes actually given that VG is mandatory and BV, CV and Sunset are all new enough that there aren't that many third-party resales out there with reservations over the next x months. So the dollars and cents probably isn't so great for them. Some companies would do this without hesitation -- we'll see what Vistana decides to do. But I have no doubt that it is entirely their decision and don't begrudge them their rights.