No one wants to jump in the hole you dug for yourself except a person with bad credit who wants an RV now and is really using your credit worthiness. This scenario usually doesn't end up well for the seller (you) because you are still obligated to pay the debt when it goes into default unless fully released from liability from the loan company.
Personally, I think you are better off to sell it for what you can and pay any shortfall to the bank and be done with it. Consignment companies like PPL Motorhomes might be another option to maximize sales price and get rid of it quickly.