No. Your best bet is to avoid these "advertising" companies altogether and sell your timeshare yourself. There are several places where you can list for free. There are some other sites that charge $20-$50 that many owners have used to sell their own timeshare. Ebay is also an option.
The so-called money back guarantees sound good, but the contract will contain language that gives the advertising company an out. Also, the upfront fees they charge are often higher than the value of the timeshare.
I bet you wish you'd have been this "SMART" when you were signing your life away at the resort! I'm glad you're so thorough in your research that you know and understand the contracts of every last timeshare resale company. Here's what...Stop complaining and blaming everyone else for your own dumb mistake.
And while your at it...why don't you take out an ad in "Auto Trader", and then create a website bashing them when your hoopty doesn't sell.
Yes, Ebay and craigslist are free/cheap..and I bet if you could sell timeshare that way, the resorts should get in on that! Instead, they foolishly spend millions of dollars in marketing and "free theme park tickets" to get people to sit in their Interrogation-like presentations. MMMM bet those powdered eggs made it allll worth it.