I am not sure what answer you are looking for, up to you to decide if you want to sell it yourself, trade it in, or take offer from CW. In the long run it may not amount to any significant difference since MSRP can be manipulated by dealer and/or manufacturer, what dealers strive for is to make customer believe they got a great deal. Just be as knowledgeable of current market pricing throughout the country, up to dealer if they want to match or beat competitors.
I never found NADA to be truly realistic as it pertains to current market pricing, and dealers only talk NADA when it is favorable to their interests, dealers always make their margin, at least those that have been in business for awhile. They always ask if you have a trade in, being deceitful will only lead to changes in final deal, again it is just part of the game when buying big ticket items in our great country.
We are pretty busy and would either trade in or take CW offer, participating in the RVing lifestyle is a losing proposition money-wise no matter how you slice it. Selling it yourself could be a major hassle, certainly will be time consuming for the nominal gain to be had with the scenario presented. In any event, hope all goes well with the sale/trade in and purchase of your new TT, and that your maiden voyage goes smoothly.