That thing should never have been approved in the first place. Leave the wealthy drug addicts up in Hollywood, Malibu, or way out in the desert.
If I were the bank, first I would fire someone (or ten people) who were responsible for approving the financing at the peak. Then look to tear it down, get the land re-parceled as individual lots, then find a builder to buy them – even if it means sitting on them for a while. Under no circumstances would I put all the furnishings back in and try to sell it as a single property again.