The Fat Finger does not reduce the dead spot, it just moves it. Hopefully to a note that bothers you less in a specific situation. If you're lucky you may get it in between two notes, so that you have two milder "deadish" spots instead of one pronounced dead spot.
I recently stumbled on this thing, though, and it intrigues me:
https://wolfterminator.com/dead-spot-eliminator-electric-bass/
The concept seems sound.
If kwmlondon is annoyed enough, he might want to take one for the team and try it out. 😃
(And report his findings here, of course)