From Fullers point of view, the best they can do is win and get a few extra $$$. Not a bad deal, but not a whole lot of benefit. They'd just get winner money instead of runner up money. TV crews are gone and no more audiocast so publicity is over. Dragster ships on Wednesday/Thursday so I would guess that the cover is already done, plus there are others could get the cover instead of Fuller. They have to risk parts breaking, a crash, or who knows what could happen. Plus it puts a Kalitta car out of the countdown.
Honestly though, I don't think Doug would want to get in like that. Doug and Connie are buddies and I seriously doubt that he would be happy to screw them like that. I haven't asked him, but I'd bet that Doug would rather earn it than have it handed to him.
David Powers has a tough call to make, I hope it works out for them.