Part of the sales process is transferral of the timeshare to the new owner. I do not know of any timeshare that will allow a transfer where there are fees and penalties owing.
Also, check ebay to see the "rock bottom" value of your timeshare and check Redweek to see what others are selling for in a "middle" market. What I would advise is to pay up the fees and secure a top notch week and then you can advertise it with the selected week - try using Craig's List in the location of the timeshare as well as Redweek and/or ebay. However, if you use ebay, you must have a professional looking ad to compete. Describe the advantages of your timeshare and what would make it a fun purchase for a new owner rather than concentrating on your own need to get out - that is a salesperson's kiss of death in my mind as no one wants to inherit financial problems. Lastly, you might see if you can make better use of your timeshare since it is yours. To do that, keep reading on the TUG board. For example, one of my timeshares is a very good So Cal summer week but it has high maintenance fees and this last year it was a real struggle to pay them. I have always been able to rent it, however, on Redweek and this year the resort rented it so that they could rerent it. It got the maintenance fees paid and a few hundred dollars in my pocket. Good luck, Funtime