If the timeshare developer is "holding the paper"---that is---is keeping the contract for the timeshare, you might want to explain your situation to them, and see if you can "just walk away" from the contract, and the developer takes back fulll ownership of the timeshare. More than likely, they WILL NOT want to do that.
Then, if that is the case, you could explain to them, again, that, due to your new situation, you cannot afford to keep paying for the timeshare. Tell them that you know it will hurt your credit, but you have no other choice but to stop paying for it.
Your credit rating (probably) will take a big hit, but you have to do what you have to do "to survive". If the facts are explained to the developer, it would be in the best interest of them to "take back" the timeshare---would be less costly for them.
If a "third-party" bought the note, you should inform them of your situation, and see "what can be worked out". Many times, the "third-party" is also affiliated, or wholely owned, by the developer.
I believe it is amost "always best" to inform a creditor of "problems", rather than to just "stop paying". They don't know your situation, if you were to no longer make the monthly obligations, and would just assume you became a "deadbeat". Keep everybody informed.
Tony